It weighed 3100 with the iron headed 340 in it. Culturally has 3.91s and 275/50/15s. Motor would be an aluminum headed stroker not built yet. Big solid roller cam. Try to tickle 550ish
That sounds like a killer deal on that fish and you should jump on it!
Mine weighed 3050 with me in it and has the same 3.91s and 275 DRs. With a worn out 904 and 2500 converter it ran 7.20 / 97 in the 8th with a 1.65 60'. That was with a 500 HP hydraulic cam 416. You will need that 60' to be around 1.50 and like Brian said 550 HP should get you in the 10's.
I am currently in the process of copying the cam / heads of this motor which sounds about like what you are looking for. Mike's solid rollers are little gems.