What valve cover gasket will work for me 91 or 95 sentra
Neither. SR20DET RWD dosen't share the same gasket as the FWD SR. Reuse the OEM gasket. Use a little RTV around the cam seals.
How much do i gap my spark plugs (ngk bkr6)
Depends on boost level... Just gap them down to .030 and be done with it.
An for the coil pack should i use 300zx or maxima's
I've got a couple SR coil packs laying around...