Thanks for the feedback guys. I ended up giving the nut a few sharp taps and it came off in one piece.

I'm leaning towards getting a Vibramate to attach the Bigsby, to guarantee a fit - unless someone else can chime in and save me $150.

I tried for a diluted mahogany stain (roughly 30% concentration) but it came out pink lol. I have some walnut stain so I'll experiment getting a redder tint on some scrap wood. Another issue that came up is some glue spots that I missed - annoying because I rubbed the guitar down with a damp cloth before hand, and found another glue spot but missed these ones. I'll try removing the spots with good off/re-stain, but since I'm not that impressed with the veneer I may end up sanding it off. I sanded the veneer off another Pitbull body and the there underneath was lovely.