You all realize that without the 3 SSME's for ballast... the damn thing won't glide worth a chit... Gonna have to strip some weight out of the nose to make that weight and balance work...
I still think the X-37 solution is the best option. Place the whole shuttle inside a payload fairing and be done with it. Using that approach, it may even come in under budget.
If removing the ballast isn't enough, just redo all the avionics with hardware made in this century and you'll strip tons of weight (complex? expensive? minor details)
Shuttle without engines, reusable boosters. Wouldn't this turn into Buran?
Okay, I've got one for "silly things to launch"... or actually, more like "trolling things to launch": .... A full-scale mockup of the New Shepard. Nothing that actually flies, just something that looks suspiciously similar. It's 20,5 tonnes, easily within the FH's payload range. FH could launch it to GTO