Another timing question.

[Dm1pfoy1]

I have 383 with stock 350 heads 625 cfm demon carb 204/ 214 or 224 ? @ .050, .420"-.442" 112 lsa cam with TH350 and power brakes.So I have timing set to 0* with vac line pulled as of right now my timing markers only go to 14 or 16* advance and I am not going to worm my way in there to some how mount a wider degree marker to block. I am pulling 12*-14* on vac advance from what I can tell. So from what I read 36* total time is what I need. That would put me 24*-22* idle timing. Since my markers dont go high enough and I don't want to ruin my engine how should I time vehicle?

Vac timing comes to mind @0* I am right about 10-12 lbs of vac. I am unsure how to vacuum time a vehicle. I want to get this right and I am assuming all other fuel portions are within tune what options are there or how do I time it?