got a question,i brought my motor to top dead center on compression stroke the mark on the ballancer pointed to zero also i dropped in distributor pointing at the number one cylinder and made sure the rotor was pointing at the number one tower on cap,started the car and set timing to 12 degrees with vacuum advance removed from dist.shut it off tightened down dist.started rechecked it was at 12 degrees BTDC,reconnected vacuum advance and now the timing mark is no where to be seen I'm idled at about 1,000 rpm also but when i put the car in gear the idle drops to about 500 rpm and when i give it gas it wants to cut off I'm stumped so if you can be of any help i would greatly appreciate it.thanks in advance.

Looks great gotta love those G-bodies.