Hi
Check out the megasquirt link in my signature. The stock fuel pump will work just fine. I kept my stock fuel distributor intact and replaced it with another one that was completely gutted. This made room for the EFI fuel rail. The M103 shares its bore spacing with the M104 so you can use that fuel rail with slight modifications. I would leave the stock ignition system in place for now and just focus on fuel. Get it tuned right and then move on to ignition. You can get in way over your head by trying to tune both at the same time.
good luck
Justin

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