I am converting a frame that has a threadless bottom bracket, which I am in the process of threading. But I'm not sure what my options are since my last conversion was far more straightforward (english treaded off the bat). I don't think English/ISO threads will fit, but it is likely that Italian threads will fit (slightly bigger). The thing is, the BB shell width is 68 mm, so the Italian (70mm) would leave a 2mm gap...is that likely to be a problem? Hopefully I can leave the gap on the non drive side so as to not screw up the chainline? Or is it possible to use Italian cups with a English 68 mm bottom bracket cartridge with the proper spindle length? I know I need a 107mm BB for the proper chainline. This BB stuff is getting me pretty confused, so any help sorting it out would be greatly appreciated.