Not without an incredible amount of modification. 1962 Beetles use "swing arm" suspension. The transmission has the axles attached through U-joints. At the wheel end, there is a spring plate with a hole in it for the axles to pass through. 1974 Beetles have "independent rear suspension." There is a constant-velocity joint on both ends of each axle, there's both the spring plate and a diagonal stiffener, and there's a bracket on the frame to hold the stiffener.
Not without a huge amount of work. Until 1968 VW used swing arm rear suspension. In 1969 they changed to Independent Rear Suspension, with CV joints.
No.
Since both cars are swing axle, the transmissions will interchange.
1974 was the first year of energy absorbing Beetle bumpers. You can't use earlier bumpers on 1974s.
Yes, since that's a tautology. Unless you mean "would additional seats fit in a vehicle without taking the original seats out first", in which case it would be a pretty tight fit, but you might be able to get them in the back. There isn't much room in the "trunk" (which in a '74 beetle is actually in the front), and I doubt you could get them in there.
Original size is 165R15, equivalent size is 165/80R15.
correct it will fit. be sure to take lots of pictures before you pull all of the wires off. so you have a diagram of where they go after.
The 1975 regular Beetle windshield will fit the 1971 Super Beetle.
a 912 Porsche engine will fit in a beetle
Probably not. The larger engine and 12 volt system needed more room. Beginning about 1967 the rear deck lid had a camels hump.
Yes
1965 to 1979 is the same.