[Learjockey1]

Guys, I am looking to buy a fuel air meter to dial in/ check my new Survival Motorsport Carbs. Looking at the Innovate MTX-L single probe ($200) and the FAST Dual Probe 170402 ($360) to use on a 427 FE with older Holman and Moody 2x4 intake and ERA Stainless Specialties side pipes (they leak out a little at the slip joints, but seem to blow out as viewed by the residue).
Questions:
1) Are there certain cylinders that run lean on a 427?
2) Best place to weld the bungs, collector or individual tube?? I guess I better have the pipes sealed at the slip joints, right?
3) Do I need a dual gauge or just check/set one side at a time?
4) Any other insights specific to this application or my choices in meters for testing purposes?

I do not mind buying the dual probe gauge if it allows better results.