You forgot about the GM 6.2L diesel, Jerry. That same engineer decided he could convert a gasser to a diesel engine which resulted in a POS.
The 6.2 wasn't a converted gas engine, you are thinking of the 5.7N olds 350. Made lots of money on those beasts, probably seen more of those scatter than anything else in almost 40 years now at dealership.
The 5.7 was available in 1/2 t 2wd pickups thru '81, had a 500 lb payload. The also made a V6 4.3 based on the V8, had more head bolts but still ---
The 6.2 diesel was bore out to 6.5L & went to the biggest pos EFI system, the DS series Standyne pump in '94.
Thankfully, Isuzu came to the rescue in '2001 with the 6.6 duramax.
