3g alt. swap problem

[SuperCleanLX]

alright ill start off saying the car im doing this to was built to be a full drag car its a gutted 92 fox every things has been re wired

well here the deal its a buddy's car he bought the car with a rather tame rebuilt 302 im mean this car is fully gutted barley any dash left

he put a elec. water pump and elec fan its a carbed car with elec fuel pump and trans brake

well his alt. took a dump and he wanted me to help him out with it so i stupidly mentioned this 3g upgrade that everybody is doing

so basically went off with 2 wiring diagrams(the 92&95) and printed off the tech article from mustang central and did every thing that should have been done with the stock wiring harness got everything done. now it wont bring the volts up past 11, goes down to 8 with some assesories on

i know the batt is not doing so good and there is a bad draw in the system but it should still idle at around 14 volts even with a smoked batt. but heres the deal i talked to original owner who lives over a state away and he said he wired it someway to get more volts out of the stock alt and now he cant remeber what exactly he did

so im trying to figure a way to get this to work even if i have to re-wire it, anybody have a suggestions on what i should do next?

what i dont get is it worked great before the alt took a dump so with little changes i did in wiring it should of worked