Not at all, this is actually my third big block 4 speed 70 monte. All 3 were the same, M-20’s, 3.31’s posi rear 12 bolts. I currently have hooker headers on it. Long tube with the bigger pipes. I believe they are 1& 7/8 this. I might be misremembering.
Thinking about switching to some block hugger headers for more clearance, 1 the steering column and 2 brake fluid distribution block, both are very tight with these headers.