so im doing my first fixed gear project with a 75 schwinn contenintal and i know i need different wheels and cranks, my problem isnt in the wheels but what size bb i need, everything is in a different dimension than what Im used to with bmx. I have what i call an american or standard bb bracket but everything i look at is in either mm or cm. Ive tried to get a conversion through google and other searches but nothing is ever consistant with what I learn. ive also been considering the ebay conversion kit with eighthinch conversion. keeping in mind that im just starting is this a decent deal if it will fit my bb? Im on a budget and know from bmx how building up a bike goes so im not expecting perfection, just not trying to waste money.

Thanks for any input!!!