I don't know if Shimano bottom brackets are compatible with your cranks. I say this because people talking about FSA cranksets said it took FSA bottom brackets. In any case, I read the new BB-UN54 is not only better than the BB-UN26, I read Shimano combined the best qualities of the BB-UN74 and BB-UN26 to come out with the BB-UN54. So, this is the end of line for that series, but apparently the best one. Usually, square taper bottom brackets are compatible with all square taper cranks.

Having read all this, I'm glad I did not install my cranks yet. I thought about doing it on my own, now I'm having second thoughts. Hehe, might be a bit better to be safe than sorry. I might also have the headset installed by a shop as well.