8 3/4 vs Dana 60
that 8 3/4 will break as soon as you get the car to hook up. along with the driveshaft. i believe the 8 3/4 is rated about 550 hp... and i twisted my stock driveshaft at about 475 hp
an auto trans may strech the numbers a bit ... but i would build the dana and have a heavier tube shaft made ....the damage done to my car from that shaft failing was more than the cost of the shaft i had made afterwards....just my opinion.....good luck