Thanks to everyone who posted in response to my questions.
The deal is done, I installed the Evaporator, expansion valve and new rec-drier at work last night, and stuck with R-12 for now. If anyone wants a 'blow by blow' posting on how to R&R the evap in a Gen 2, along with part numbers and O-ring and hardware listings, let me know and I'll write up a service/job description for the board. I used no air tools, took my time, and put the system under a vacuum for 25 minutes since it had been leaking for so long and was now also open to outside air with the repair work. Total time was 2 1/2 hours, start to finish. <img src="/forums/images/graemlins/cheers.gif" alt="" />