The reason I asked my questions were due to a freind of mine having a 8-3/4 in his all steel 69 Dart except the fiberglass hood that had a 500 inch Indy headed big roller cammed etc.... You get the picture. He wasn't fooling around with his street ride.
My engine isn't at that level.
The car was heavy. The car ran into the 9's. How deep I forget. The 8-3/4 did break. The big enemy was weight. High rpm launches don't help with slicks but this is where he was at. The rear was unbraced with street gears, not pro gears. S/S springs were used. Off set IIRC.
My car is a 3500 RPm foot brake car. It weighs about 3200 with me in it.
Should the car be lightened and the rear strengthened and the launches not track brutal all the time, the 8-3/4 will live for a long time no doubt. If the plan is more racing the car while it retains full weight, I'd look to the Ford rear.
