No.
No. It will fit the 1966 and 1967 Chevelle only. A 1967 Skylark hood will fit if you can find one.
No, the hood will not fit. 1965 is pre-Super Beetle; 1973 is post Super Beetle. The 65 hood is going to be much more narrow and arched then a Super Beetle hood or anything past their early transitions to the Super beetle which started to transpire in June of 1971
Yes, the hoods from 1968 to 1979 will all interchange.
Probably not. The larger engine and 12 volt system needed more room. Beginning about 1967 the rear deck lid had a camels hump.
no
No.
1974 was the first year of energy absorbing Beetle bumpers. You can't use earlier bumpers on 1974s.
YES.
Since both cars are swing axle, the transmissions will interchange.
as long as you can get the latches in the back of the hood to match up as well and the hood latch in the front you should be good.
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.