Depends on the size and enthusiasm of the clowns involved.
Four.
10 people
None will fit.
You can fit quite a few. Here's the web address for one: http://www.partsgeek.com/catalog/1973/volkswagen/beetle/carburetion/carburetor.html
Nine
clowns! clowns! clowns!
Same answer as how many clowns fit in a clown car
two usually, but if your all clowns, you can fit approx. 8 people
The 1975 regular Beetle windshield will fit the 1971 Super Beetle.
They experiment with who can fit where and how, then they practice a lot.
maybe 3 or 4
No.