RE: F6F Hellcat
There are several posts on panel lines here in the forums. It's been covered extensively. Do a search. Specifically, for overlapping panels, instead of using a thin tape with a primer buildup on both sides, you use a wide tape and do your primer build on one edge of the wide tape. Layout your tape in a manner that puts the overlap appearance in the correct direction.
Again, do a search. The posts I have seen have great graphics included.