How many amps to relay? Anyone Know?

Right, but depending on how the bypass was done, let's say all he did was jumper the two ammeter connectors together "or not" and ran a big charging wire from the battery to the alternator

This means (in the diagram) BOTH the black (former charging wire) AND the original RED battery lead now act in parallel as "battery feeds into the car.

BUT if either/ both of the bulkhead connectors for those two wires are "iffy" the red one (fuse link) especially, could make enough head to blow the link

ALSO if you do this bypass in this manner, if the black charging wire is left in place, and IF the bulkhead feedthrough is repaird, YOU NO LONGER have the protection of a fuse link, because current can flow-----

from battery -- through bypass wire-- (battery to alternator) -- back through charging wire through bulkhead -- to feed system.