Motor question

I have a '74 Super Beetle and a '71 Beetle.

The motor in the '74 motor is excellent and the '71 motor is marginal, and I'm wondering if they are interchangeable if I wanted to swap one from the other. Both engines are original.

Are the carburators the same too?

Any advice is much appreciated.

off the top of my head, i can't think of any diffrence's except for a cc diffrence. other than that, they should be the same case. i know busses have a diffrent case, but bugs have the same thing. hell, we have no clue what year the case in my dads race car is, but i think we use a tranny out of a 67. they're swapable. unless you've got a vanagon engine. the late models in the 80's have water boxers.

Engine should be able to be swapped with no problem and they should both be 1600's.