hardware anad service numbers

[jason k]

hi I have a 95 f body I installed a 6.0 in and was using the pcm from that truck for the swap. I now put that truck back together with that pcm . so I installed a pcm of different service number and hardware number from an express van I had around to keep my cable driven throttle body but the express van pcm doesn't have a tach out on that one but my truck did. can I use my j programmer to put the 12576106 service number 12570558 calibration from the truck into the express pcm 12586243 / 12583659

what determines what factory calibrations can be loaded into what besides the obvious 24x vs 58x and idle motor drivers and red and green connectors??
thanks

[RandomEnthusiast]

Is the pinout physically different on the pcm or is it the same? If it's the same pinout I would think it uses the same processor and maybe even the same hardware aside from hardware revision. But I would double triple and quadruple check. On the old obd 1 stuff I know 93,94,95 trucks pcm's are interchangeable as I have done it. It was just hardware revisions and addition of features such as tcc pwm lockup and linear egr.

[jason k]

Some of the pins are different and the main issue is there is no tach output from the pcm on the express version and when I installed it I left the pin out the same as a truck configuration I had no signal from that cavity on the pcm

[RandomEnthusiast]

I'll be very careful trying to flash it over then. It may be compatible but I would be cautious.