Couple of answers for you..
Yes you can change out the coils and wires, though I know of one member that has had problems with the high performance Accel coils (one arrived DOA, the other coil shorted a few months later and took the CDI with it)
As far as spark plug wires, we usually build our own with wires and boots anyway
There is a write-up available if needed
You do not have to rejet when changing pipes. You only have to rejet when changing the air intake such as when you do an ear shave.
Rick is Rick at Rick's ( http://www.ricksmotorsportelectrics.com/
Patriot Guard Rider
2000 VN750 Sere (Serendipity)
1990 GL1500 (Ole Blue)
1986 VN750 EVie (project bike, heavy custom)
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