I think aluminum welds tend to be weak points so that is another reason for the glue.
I have a holley 2:1 regulator. I have my PL box almost maxed out on the grn/blue setting. It runs real good a WOT but shouldnt have to max the box out. If this final air leak will not solve the problem then the box may need to be set up to run richer or maybe turn the fuel pressure up. I am at 42psi right now. I spent all winter putting the thing together and tearing it apart. Sled has less then 150 miles on motor right now. Lots of work, but fun as hell to ride. Still few things here and there to do. I should be welding it tonight and then see what happens.