Mazel Tov on your first Super, guy! For Beetles, I've only really ever preferred Supers. 1974 is, actually, my favorite year in S.B.'s. At that point, in my opinion, the Super had reach its pinnacle, prior to becoming fuel injected the following year. Not to impugne F.I., for they're great, but I'm speaking of the original, carborated jobies. Type 1303's are excellent cars!
Yes, mine makes the same "clunk" on the same side, but only if I'm breaking and I go over a rough bit of road at the same time. It's the rubber. I need to get under there and replace it soon! My Type 1302 Super Beetle is my daily driver, however, and it's some times hard to prioritize when to take him off of the road long enough to work on his little foibles.
Is your car a fully manual transmission, or a 3-speed Auto Stick? Depending on this, and a few other variables, your problem could be anything from timing, to the shifter forks in the tranny, to the nose cone on the tranny. Lots of knowledgeable people on here, and many resources from which to derive information. Not to worry, either way. It's a fairly common condition that can be remedied, depending upon the source of the problem. I'm a novice VW owner myself, so I'm only learning as I go along too! I won't pretend to know the answer.
"Dub" gezunter heyt (Dub in good health)!