Which ECM should I use?

[dave w]

Is there a doc to show how to hookup a computer on a bench and program it without it being in the car?

With very few exceptions (94/95 LT1 computers), 1986 - 1995 OBD1 computers use chips.

Moates.net is a good source for software and hardware to program chips. http://support.moates.net/beginners-programming-chips/

Getting started: http://support.moates.net/obd1-gm-getting-started/

dave w