340 x-block vs. 410 stroker ?

Hood probably 60 lb? I took 53 lb out of each door. So I just added a hundred and six in doors. It definitely took two people to get the front bench seat in. I was able to get the rear space duster back seat backing has a big metal plate on it. In a Big Tub I had the seat belts and was quite heavy when they were all in there together now that I think about it.
So many don't realize and think "A-body" = feather light. But if you have the fold down rear seat, braces in doors, and the "reinforced" bumper/shock absorbers, and power steering those a bodies are as heavy as a '68 Satellite B-body.

Now, that all being said, you'll be just fine. You had the mph, so the power is there....