I have an old TA crankset 170 arms in good shape - it is set up as a triple 54-40-28. Blasphemy or not I want to put it on my 2011 Soma touring bike set up as a double 44 - 28 double with modern chainrings. I also want to get a sealed bottome bracket. I figure you vintage guys are the best to handle my questions.

So questions
1. Can triple to double be done? How?
2. What bottom bracket do I need?
3. Is Rene Hearse out of Colorado the best place to get modern rings?
4. Is there an outer ring chain guard that doesn't cost a fortune? (which makes it a triple).

Thanks ahead of time for your help!