Anyone want to talk Chevy! LOL

Just leave the engine as is and rebuild it properly. Maybe shave the heads a hair. I took a 307 Chevelle from that year, about three years old, and held the throttle to the floor. in neutral, for five minutes. Thing didn't have enough guts to blow itself up. Took a '70 Chevelle from Fremont, Califronia to Reno. Going up the hill floorboarded in spots it actually got over fifty mph, with two people in the car.
I had a '68 Chevelle with a 396. That would be the engine I would recommend.