Can't be BB30.
Theoretically, no problem with the conversion. But naturally that assumes you select the correct components and put them on correctly. (Meaning tools as well as procedures.)
Speaking frankly, though, this is a dumb idea. Just buy a bike with the components you want and be done with it. It will cost less - probably a lot less - and you'll have something to ride instead of having your bike in pieces.
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Stupidity got us into this mess - why can't it get us out?
- Will Rogers