Where to start? 1969 Camaro getting interior components from a 2011 Cadillac CTSV

Looking for some direction if anyone could help. I am one of four working on a new project. We bought a GM Performance LSX Supercharged with a Connect and Cruise 4L85E automatic transmission. The car we are building is a 1969 Camaro but we are using as many of the interior components from a 2011 Cadillac CTSV that was hit in the rear. We have the ECU and TCU that came with the Connect and Cruise package, but we also have all of the wiring harness from the CTSV including ECM and BCM.
Our two main hurdles as of now are fuel gauge and ignition. The fuel system on the original CTSV has two signals coming from the tank, they get averaged by the ECM and sent to the body control module (BCM) then sent onto the gauge via a LAN connection (as far as we can tell). We would like to use the stock fuel gauge with an aftermarket tank and fuel pump. Does anyone know how to use the stock fuel gauge with this set up? Secondly, the ignition. As far as we can tell the ignition on the CTSV has a 5 volt signal that is sent to the ecm then onto the body control module which sends a signal to the starter (once again via LAN connection / signal) for starting the engine. We would like to use the stock steering column, stock key fob and as many other oem / stock items that we can from the CTSV being installed into the 1969 Camaro. Any direction would be greatly appretiated. We could always give up and use a standard 12 ignition signal and an aftermarket fuel gauge. Thanks again.

Good luck with the project. Coincidentally I had a 67 Camaro that I sold and bought a 2012 CTS-V but this is over my head. Sounds like a nice swap.

New direction on the project. 1969 Camaro will get 2011 Camaro interior with the same engine as the CTS-V. Ordered as an LSX with a supercharger (LSA if you will) and 4L85E transmission. Will be using the 2011 Camaro ECM and BCM. So far everything will work except for spark and injectors. Still working on that part. Here is a mock up of the interior in the shop.Attachment 54303 and one more just to see what we are dealing with (sub works). Attachment 54304

As long as the crank trigger & reluctor are the same swap over the entire ignition system, it should run that motor fine without the 5V signal as long as you disable DTC's & Antitheft. The TCM should actually have two components to it requiring two power supply wires connected, not just one, otherwise it will shift - but it will feel all wrong and messed up. And the most hassle free way would be to swap the entire fuel system onto the Camaro gas tank and use a different fuel guage, or the one from the Caddy. You may be able to somehow get/adapt the stock Camaro guage to work with the newer format fuel system, but good luck if you go that route and have fun with all the extra credit homework that's involved. Your choice, would look pretty clean though. P.S. If you have the extra storage space and can have the Caddy transmission without forking over any more cash, save it for a spare. With a "simple" tail section swap you can convert that AWD transmission into a RWD model for your next project, or if you or your friends burn one up.

Thanks for the tips Dr. Nopps. Changed the config for the last time.
We sent the 4L85E back and ordered the 6L80 but for a truck. This way we could get rid of the weak rubber connection from the drive train. We also have the engine in the shop, test fitting the belts, wring harness and A/C. Here is a shot of the engine Attachment 54580.

Well at least it looked good on paper! Just kidding, had to poke fun at the plain square briefcase looking upper intake. I also forgot to mention most modern ('01 on up I think) GM fuel guages get signal through the BCM. On the cars I've seen with bad BCM's the fuel guages & radios never registered and the low fuel lights were stuck on. Cool motor, wish I had one of those to throw in my truck. Even without forced induction they produce excelent power. I'm sure you will be VERY happy with the results. Hope I wasn't confusing talking about an All Wheel Drive to Rear Wheel Drive transmission conversion, whenever someone mentions a Cadalac V8 I immediately start thinking of AWD Escalade platforms. P.S. It says at the bottom you have a 4L65E not shifting right and another project with a 0 MPH dead spot. Update sig if that's been resolved, if not I'd be happy to at least try to help out - no promises. Unfortunately my laptop fried and I have no way to view tunes, but I'm still really curious about those two issues as well. Good Luck!

@Dr. Nopps. That briefcase looking intake also known as the hat is interchangeable with the ZL1 hat which has the heat exchange tubes coming out the front of the engine and its black. Not sure if we are going to change it b/c it will be mostly covered. We are concerned about the BCM controlled fuel gauge and the fact that its not working. Tomorrow the MDI gets delivered so we can validate just about everything we have done thus far.
As for the sig, all that stuff is in the books and has been completed. One more pic of the engine and transmission...Attachment 54614

I can see where those tubes go, that's cool. I can only think of somehow jamming the fuel guage from the Caddy into the Camaro, hooking up the BCM pretty much just for that, and hand pasting the data from the fuel system section of the Caddy tune into your new engines tune. I would hope that would be enough to get it to work.

With the MDI we programmed the new ECM and TCU and many other systems that were missing. We could even fire the starter with that software but couldn't get it to the start sequence with the key. We tried to reprogram the signal match for the start sequence through the BCM but no luck. I bought 2 credits for GM, turned off both VATS and the Start Sequence hit the key and the engine turned over. Success! HP Tuners made it so that engine would work in any car. High-fives after last Saturday. BTW, gas gauge still goes through BCM. Instead of two wires averaging we used the one from the CTS-V fuel pump and soldered all three wires together (basically it is now averaging one signal instead of two). Everything works, including the aftermarket heating and cooling system with the 2011 Camaro controller switches using the hysteresis motors.