i searched but didnt really find anything. i know gns had them but seems hard to find. are there junkyard parts i can build one or repop stuff out there for a gn that aint outrageous?
No. I own a GN and no that configuration isn't good. The offset is too much. The videos I made linked above should have the information you need to build one DIY even for a 350.
Has anyone looked into the front wheel drive 3800 engines? Does any of that have the same head bolt holes?
One thing to consider is most serpentine setups spin the water pump in the opposite direction as a conventional belt system. I got burned on this way back when. I swapped a 2.8 from an 85 firebird into my parents 87 Jimmy. The bird had v belts and the Jimmy had a serpentine system and the pumps spun in opposite directions. That never occurred to me and just swapped over the accessories during the swap. The Jimmy always ran kind of warm and would almost overheat with an extended idle but it was driveable. I had a eureka moment reading a car craft article that was about junkyard serp swaps and it mentioned the pump directions... I figured no problem I'll order the correct water pump. Well the situation got a little more interesting as there was a water pump housing change between the years and there was no reverse rotation pump for the 85 engine. I eventually took the pump off and swapped the impeller. It solved the issue but what a pain in the ass for a gutless s10 Jimmy....
