Bottom Bracket Compatability Question Good afternoon all!  In previous questions, I've mentioned that I intend to rebuild my 2000 Trek 7700 Multitrack.  Well, I'm beginning by replacing the bottom bracket.  According to the spec sheet I got from Vintage-Trek.com, the BB is Shimano BB-LP27 73x113.  I've searched for BB-LP27 73x113 and come up empty.  I assumed this is an obsolete part, but there must be a current part which will serve the same purpose.  How do I decipher what current part would work in this application?  

I'm adding the technical sheet I found on vintage-trek.com.
Here's the Shimano datasheet. So we know it's a square taper, ISO-threaded BB. So a UN54/UN55 is the replacement part (take the UN55).

73 is the shell size: 73mm.

113 is the spindle length: 113mm.