Qucik question before I change to 2 bar os

[abc]

When I change to a 2 bar os from the stock 1 bar, is it ok to make most of the preliminary changes to the rest of the tune file before "write all" is done attached to the ECM?
Basically, can I select the 2 bar SD os, adjust the VE table, adjust the ignition advance table, adjust idle air flow, and for the most part a few odds and ends before I save it to the ECM, or should I change to the 2 bar os, save it to the ECM "write all" then read it back off the ECM before I make all the other changes?
I keep seeing the warnings about bricking the ECU and you know, I hate to do that if I can avoid it.

[blindsquirrel]

Open file, apply 2-bar OS, MAKE NO OTHER CHANGES, save the file with a new name. Close the Editor.

Then, and only then, you can open the new file you just created and make any changes you need before writing to the car.

[abc]

10-4, thanks for the info.

While I have you can you also confirm a few other questions I have? I went into turn off the SES light for the bank 1 and bank 2 second sensors and that option is no longer available in my version of software? Is there a work around for this or do I just cover the SES light with a piece of tape from now on?

I looked at a current file from a LS1 I have in the stable that I worked on the tune about a year ago and I know I disabled the second sensors via HPT at that time but now, even looking at that file the option is not available to turn them on or off, it's all greyed out so to speak.

Is it a simple as begging for an old version of the software from you guys?

[abc]

OK, I just searched the Google and it appears I need to take their test and agree to the terms and they will take my gray boxes away. It looks like they were able to update the software without me asking to do so? The only way to hide an older version is off the internet I assume? If someone has an older version they would like to share, I can store it on an external hard drive and only use it on a com not connected to the internet.

As far as the vehicle that was tuned prior to the update, I assume it will function as is unless I use the current software to make changes and it will likely enable the SES light again? Man, sometimes I hate change.

[abc]

OK, I have taken the test and gained access to the SES sections that were previously grayed out. Now that my software and firmware have been updated on the MPVI2 can I safely proceed with the OS change using the directions provided from Blindsquirrel with an old tune file from the ECM or should I read the ECM again to get a current file with the firmware/software update then proceed? Basically, is it OK to use one of my old reads (the original file) from the ECM?

[gametech]

Old read will be fine.