Any ideas about how to take off the top granite of a premade vanity??

I need to move it up an L shaped staircase and the length and weight with the top and attached sink make this task very difficult. With the weight of the granite top off, it actually may be do-able. I like the granite, and would re-attach once they are both brought up separately. Did I think about this before I bought it? NO!! But the deal was great!

It is glued well, and I do not want to damage the vanity by removing...

Any advice is appreciated

TIA!