If I remember correctly, line feed was triggered by a small metal piece under the carriage. When the carriage returned to the left side, it pressed a paddle that advanced the platen. It was held on with one screw, and if it ever got turned out of position, it stopped pressing the paddle. The printer can be removed and flipped over to fix it, but remember that the punch and reader are both driven from the print mechanism and are connected.
I can think of a number of things to say about this subject, I actually did discard a Kleinschmidt recently (I don't recall the model but by the designation system iyou're using it was KSR, ie no paper tape) but I couldn't afford the space anymore and it was not in good enough shape to be worth the trouble and besides all the computer museums said they wouldn't be interested even if it were new fresh in the box. I guess my first question though is if you really want to be authentic, where's your acoustic coupler? (They usually sat on top of the right panel although I think I recall seeing some that were actually BUILT INTO it, but that may have been an aftermarket upgrade.) Might make another project to see if you can find one somewhere and get that working...
It's also just possible there's still a few folks around who remember the old Model 19s (and how they could remain in active service for DECADES, frequently as the old AP or UPI "wire service" especially at broadcast stations and newspapers). When people who had been maintaining the old machines first saw the 33s you heard a lot of lightly concealed swearing about "bucket of plastic rattles" (especially if they learned THEY would have to maintain them!) which is true enough if you compare these next to the older machines which hardly had ANY plastic at all. If one of THOSE guys saw you raving over your latest acquisition they'd probably choke on their coffee, but I guess there aren't too many of them around to do that!
When I had an ASR-33 in the basement I had a program called "Fancy Punch" that was written in basic and ran on my Southwest Technical Products 6800 computer system. "Fancy Punch" would allow you to send a line of text to the ASR and have it come out as legible punched characters on the paper tape. My copy of the program is long gone, but it shouldn't be that hard to re-create it.