I have a piece of $#!T ESP LTD M-50 and have been thinking about upgrading it with the whole shabang...floyd rose, emgs, new tuners, custom paint job etc...and was wondering if i could fill in the neck bolt holes on the neck and body with some wood filler or something then glue on the neck and taper it down to make it a bolt on? Any suggestions...think it could be done? If so could i just use a common wood filler to fill in the holes? Lemme know...
Asked millions of times.

No. Won't work, you need a longer neck tenon, and a decent bolt on neck is just as good as a set neck.
I'm not very active here on UG currently.
I'm a retired Supermod off to the greener pastures of the real world.
To the best of my knowledge, it's the area of the neck that is touching the body. The part that fits in the heel. I remember someone saying if it was a perfect (And I mean PERFECT) Bolt on with nothing in between the neck and body, then it could work. It won't work on a beginner guitar. Also, let me be the first to say upgrading a guitar with bad body wood (Agathis) isn't worth it.
Teh neck tenon is hte pocket that links the neck to the body. Anyways, unless your game for a serious mod, I woudln't bother, it'd involve rupping out the center piece of your guitar, and basically remaking the pocket, as well as makeing the neck heel longer and jazz.