On my 1980 TA, I recently pulled out the stock 301 and installed a stroked 400.
I purchased the same F10193 from Classic Industries. I carefully drilled out the rivets from the original shaker removing it from the baseplate. The base and shaker were also calked together. It wasn't hard to separate and clean the calk using an orbital sander. I used rounded head screws and nylon lock nuts to secure the new baseplate to the scoop. My screw heads still need to be painted, but you can hardly notice with the hood closed.
As Roadking mentioned the 301 air cleaner is different. It's smaller in diameter and I think the height might be different too. As Roadking also said there are two different style air cleaners for the 400. Either should fit, but the one with the larger oval opening is more desirable and much harder to come by.