I have a vintage air kit in mine (1009, but the truck is the same where it matters from the firewall forward)
The compressor mounting was extremely annoying with the 24v system and I still have belt wear issues now years later.
Really the only good option is to go 12v and replace one of the alternators with factory compressor brackets, IMO. I really wanted to keep 24v and it was a huge amount of work for a system that still barely works/regularly breaks belts. I think it's because the belt length is so long relative to the pulley diameter and the diesel has such bad crank harmonics, but the v belt is always coming off the compressor and then it breaks. One time it even took out all the other belts due to wrapping broken pieces of the AC belt around the crank. Instant hydraulic and electrical failure on the highway wasn't fun... No power steering or brakes, all the alternator lights on...
Otherwise the kit is nice. Working under the dash is a pain but the install is not too hard.