...that car has many issues,..the original wheelbase was 113",...but the rear wheels sit too far forward on most original 40's, not centered in the wheel opening. You need to set up the car with the wheels centered in the wheel opening where it looks "right" to the eye. ...the orig. firewall had a notch in the center altho not much, but was better than the flat one put in. ...I'd redo that car with a SBC and sell the big block, or keep it for another project. ...good luck with it, keep asking ?'s, you'll get it figured out.