Most of the truck ac compressors are not variable displacement and can be made to work with aftermarket ac systems. There is some discussion on LS1Tech about it
https://ls1tech.com/forums/conversio...e-fixed-2.html
The problem with most OE truck ac mounts is that they interfere with the frame rail. Both Alan Grove and Vintage Air sell a mount that keeps the AC compressor low and clears the frame rail, but they use the Sanden compressor.
If you currently have a Sanden compressor from VA, I would get, or fab, the low compressor mount to use it on your new LS motor. Here is a pic of one I fabd for my truck after looking at the one from Alan Grove. It uses the stock tensioner from the truck
