installing this kit on an lt1 with crank trtigger and 1x cam sync signal is there any way to run the ls coils with the universal mpfi harness or should i have ordered the ls1 harness and modified it to fit my build? thanks for the tips in advance.
Holley 550-604N. Yes, you need the following harnesses:
The Holley 558-307 CNP main harness is for Holley's CNP smart coils and LSx coils.
If using Holley's 556-112 CNP coils, Holley's 558-312 CNP coil sub-harness is also required.
For LSx coils, the Holley CNP main harness plugs right into the two GM 12579355 CNP sub-harnesses.
There's no need to make your own ignition harness. This is much easier & a lot less time consuming.