Hi my 414 mki works fine after almost 20 years but I'd like to be proactive and replace the belts. Does anyone know the exact size of these belts? I see that I can get a kit online but 10 bucks for 3 belts is crazy. I own 40-130mm 1 mm square belts, but I think I'd at least need a large flat belt for the capstan. Is this a relatively straightforward repair or are there any surprises? For instance I've had random parts fall out of cassette decks during repairs that I just couldn't guess where they go, and without a service manual it was rough. Any other parts I should replace while I have it cracked open (and do you know the size/specs)?