New best so close.....

Yes. Car weighs 3420 with me and 5 gallons of fuel. That mega block/browell bell/Lenco and Dana 60 are all heavy
And yes MW Stg 6 heads with 4150 flange M1 RB set up 528 Cid Wallace calculator shows between 650 and 675 hp. Engine dyno pulls showed 707
How much roll cage do you have ? 10 point?