Ignition Fusible Link Blowing after Lean Burn Conversion
You need to troubleshoot by picking 1 problem and trying to solve it, then work on the others. If you cannot solve that one, move to another. I thought sure you might have had something when you were looking at the fuel pump/ oil pressure switch. Unfortunately I don't have documentation on what you are working on.
DISCONNECT questionable stuff and see if you can eliminate the high draw, and if not, leave the loads disconnected. For example, on the ignition circuit, you don't need the choke nor the alternator to troubleshoot that circuit, unless 1 of them is causing the problem, which it could. But disconnec them to see if the problem drops, and if not, leave them off line to not over-complicate the problem. Bear in mind that AKA if what you disconnect was drawing normal current, such as the VR/ alternator field, the load current WILL drop, but it should not "cure" the short/ heavy current problem
Obviously, if you DO have a good diagram, one of the first steps is to document just what all IS on that circuit