#2
Sort of. I did it on my partscaster.
There will still be the old holes that may not be covered and need filling.
If you're happy with just diving then mounting it flush should pose no issues, as long as the saddles remain the same height. If you're after some pull-up then you can raise it a bit, but you may need to shim the neck to compensate, or you can rout some space underneath.
Every case is probably slightly different though - do lots of measurements and see if you can work out what you're up against.