Will an 8 1/4" bolt right in to my 7 1/4" spot?

I swapped an 8 1/4 into my 68 B'cuda w/ 318 and 904. My existing e-brake cables are the type that has a single cable coming back into a 3-4" bar. Short cable to left side, long cable to right. Everything fit.
I used a driveshaft from a 78 Aspen. No cutting or shortening involved.