At idle there are two small screws between the fuel bowl and the main body (known as the metering block) There will be one on each side of the primaries, none on the secondaries (most likely a plate instead of a block). In is lean, out is rich (on most models). You want to maximize vaccum which is usually 1 1/2 turns out from when it GENTLY bottoms out.
As for the transition circuit, you need to either tap into your passages and put screws there (which is a bit into it for the transfer circuit even though I have done it).
The main circuit will need to have it's jets adjusted, smaller leaner, bigger larger.
There is much more detailed info here
http://www.bob2000.com/carb.htm
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1984 WS6 Hardtop Trans Am
Former L69 Car under restoration
1984 T-top Trans Am
4-bolt main 350, performer intake, headers, Holley 650, T-5, hayes clutch, dual elec. fans and 3.23's.
Daily driver and restoration
13.98 @ 101
