multiple questions 74 crew c30 dually

[jmosesgarcia]

Hey everyone I'm not the best mechanic out there as i'm only 20 but i learned alot since the age of 10 I have a 74 crew cab dually c30. I want to put a lift kit on this beast about 2 inches or so not to much because i still like ride comfort will this screw with towing a 42 ft gooseneck? And with that I still need it to be extremely heavy duty because I added 2 springs on the rear stock axle

Another thing is and air bag setup underneath the truck with attached aircompressor. has anybody used these? Id like to put these on. What do you all think?