tuning my 350

[BamaDave]

I am trying to tune my 350. Like I said it is a 350 with a Holley 80555 650cfm carb and Edelbrock Performer intake. It is a spread bore carb. I don't know what cam is in it but it has a lope to it. When I tried to see what the timing was I couldn't see the mark on the crank damper. What should it be at? Also, when I hooked my VAC gauge up to the manifold vacuum was between 10 & 15. Idle was about 1000rpm. With the jets 1 1/2 turns out, if I tried to turn down the idle, it died. Lowest I could get it and keep it running was like 900rpm, but it was real rough, when put in gear it barely ran. I am also concerned with how the gauge read. When I first started it was steady, when I reved it, it would go way down then back up. Usually when it went back up it rarely stopped in the same place it started. After fiddeling with it a while it started a quick bounce between 10 and 15. I am pretty sure I was hooked up to full manifold, but the cruise and AC control VAC was hooked up to it too. I just bought the gauge today from AutoZ. and the needle when unhooked starts on the fuel pressure side of the gauge on 1. I will try to get pics. I know this is long but I am freakin' out. I don't want to have to tear into the engine. I have a rebuild kit on the way for the carb.

PLEASE SOMEONE HELP!(edit-what is the thing circled in 2nd pic? 3rd pic is where I got mani. vac.)