if u wanna check for a leaky injector, energize the fuel rail, hook up a fuel pressure test and let it sit for a while, if it bleeds down u obviosly have a leaky injector, also check the spark of the affected cylinder

 

Keep the timing at stock 10* and fp at 39-40psi and go from there. Any competent tuner will take care of timing and fuel adjustments through the tune which is done with a chip FYI mattdel.

Are you sure you didnt bend up your timing pointer when doing the swap causing the timing to be off? I am not saying it is the cause of your glowing headers, but you dont need that much timing.