Chainline on a trek 660 fixie conversion I am converting an old Trek 660 frame to fixie. It takes a 68mm bottom bracket and I'm putting in an SKF bottom bracket (like this) with both a BMX profile racing 110mm 46t and redline BMX cranks 165mm (like this). 

Now I talked to my friend at my local shop and he says these older frames run 110mm. I've looked on the internet and I believe he is correct in that I can use a 110mm bottom bracket and use spacers if need be to get the correct chainline. But I've also read that I may wanna run a 113mm bottom bracket. 

I was wondering if there were any gurus out there that could help me out? I know that it's only a matter of 1.5mm but I just wanna get it right because the bottom bracket I'm getting is mailorder only and $129, so I'd like to limit my mistakes on this build.
There seems to be a bit of confusion in your question about how chainline is measured, and it's relationship to bottom bracket spindle length and the rest of the bike - you haven't given enough information to answer your question.  The rear hub and sprocket's chainline measurement is required to decide how to adjust the chainline in the front.  Even then, the published information about chainline for most cranksets (including the one you have linked) is scare at best.

The easiest thing for you to do would probably be to acquire a used/cheap sealed cartridge bottom bracket in your desired length and see how things measure up.  Once you've made measurements, you can lock in the size for your SKF.