Hei Swap with Toyota Alternator
... Currently my IG goes from Alternator to resistor and from there to ECU box ...
Part of the confusion is that above description is not exactly right.
IGN goes to the Alternator, it is not an output.
You will not use the ballast resistor w/ HEI. You can remove it and replace with a jumper in its place.
You need to run IGN also to the HEI module. You can tap it at either end of the wire, wherever closest to your module. If you run a new blue IGN wire, best to use 12 or 14 awg for any section shared by the alternator and HEI.
Re wiring the "sense" wire of the Toyota alternator, the instructions suggest connecting to BATT+ (big stud on starter relay), but I would be concerned that might draw current when off and run down the battery if sitting for weeks. Research if you can connect it to switched 12 V, which under-hood is only the IGN wire. If so, connect the furthest upstream you can tap, i.e. as close to the bulkhead connector as you can conveniently, ex. the upstream side of the ballast resistor connector. It can be a thin wire, since just sensing. I would download a 4 Runner schematic and copy what they do.
From the description, it sounds like the Toyota alternator doesn't require a "bootup" from the dash lamp, as do older GM's (post 5, #5). That was the "Motorola type", which my 1980's M-B cars also use.
