'70 & up flat reg with the triangle connector and 2 field terminal alt correct? If you unplugged the reg triangle connector & it's still charging then the alt has a dead short in the field circuit inside it or the nearby green wire brush assy or the green field wire from alt to reg is grounded one of which is makeing it full field (max voltage). Less likely that it is the green wire since the reg end of it is disconnected but check the loom along its' path. Even with the reg unplugged the alt field is still being fed fire from the blue wire to one of the alt field terminals & it's puttin out max voltage just like it would when a parts house tests it. That high of voltage will FRY your electrical system. Keep run time to 5 seconds max just long enough to take a reading on the VOM to see if your changes have got it taken care of