STR-12 manifold help needed

I bought this manifold for a new ground up build. My problem? Cam and carbs for my application. How to build enough vacuum for the street and not be a dog at the stip (street strip but more strip). Here is some basic info,
68 gts 3500
69 340 .60 over
4" stroke
11.8 probe pistons
B1Ba heads (no flow# yet)Milled to 63 cc
8" 4200-4400 A1 conv.
727 RMVB
8 3/4 w/4:88 spool
Caltracs
M/T 275/60/15 (28" tall)