HI, I purchased a Hakko FR-301 Japanese version (I'm in the US) and performed the conversion of removing the 10 Ohm resistor and replacing it with 2 300 Ohm resistors. I was at work when I did it so I was kind of in a rush (on break). Everything seems to have gone fine and the Hakko is running the motor at the correct speed now on 120 60Hz US but I have a question. The case halves don't seem to fit together perfectly, in most places I can squeeze the halves and see a little play. I've taken the thing apart 2 or 3 times now to make sure there were no wires getting in the way and I don't think there are but can't be sure. I don't want to tighten the screws any more or keep taking this thing apart as it's plastic and well, while a seemingly high quality plastic, still plastic. I didn't think to check the fit before disassembly and the gun is working fine but my OCD is getting the better of me. It may just be the halves are a little out or warped from the molding process but if anyone has one of these can you see what yours is like and post back your findings?