Assuming it's a stock plastic knob, soak the knob in hot water to soften the plastic. Than take a rubber mallet and hammer it into place.

I did mine in the '72 without soaking, but I imagine letting the plastic get hot and soft will help matters.

Jeff


My 1953 Chevrolet
1947.1 Gallery
1972 C-10 1/2 Ton & 1972 C-30 1 Ton