guesses only:
keep at least 1" away from seam so fixing either does not interfere w/ other.
by far most likely location is all along deck and this is least likely location to hang up gear etc.
assuming peg rail is below seam, plan on transition near cockpit so can access/repair/install more easily. then on assembly just have to slide in pegs to already installed rail. and add some glass tape(intermittant pcs or full cover-maybe even goop) to restrain cable transition in this one area after yak together.

while tempting to combine, i would keep away from the seam.
-mick