1972 chevy super Cheyenne help

[Classicman]

I have a 1972 chevy super Cheyenne 402 big block, C10 400 turbo hydromatic transmission. I rebuild the heads and I tried to set ignition timing but was little difficult, I can't set the right time. Also, I bought a new carburetor for this chevy 72. I need help with the vacuum lines diagram and idle mixture for this new carb. the old carburetor is different in vacuum lines and I discovered that was made for chevy 73 and all vacuums lines are different from the new one.( I don't know if the last owner replaced this carburetor or is original.) I going to see if I can set the ignition timing and drive around the corner. Thanks.