Hello. I have a 1990ish ross centaur frame I want to make into a single speed. I got it as just a frame set so I don't have the original components.

I want to buy a new bottom bracket (prob just a basic shimano), crankset (basic sugino or similar), and i was thinking to buy a mavic cxp22 wheelset with a flip flop track hub from velomine. the rears spacing on the frame is 130mm and velomine says they'll add axle spacers for free so I was just going to do that rather than cold set or squeeze it.

now my question is: How can I determine spindle length that will give me a proper chainline? i don't have any of these parts in my possession and don't have the original bb to even know where that one was at. I want to try to do this myself and find some of the stuff used or for deals online and want to try to avoid getting bailed out by lbs if possible.