It's been asked before ( I know,....I asked)
As I understand it, they won't do it because the Modern Construction neck wouldn't be able to be used since the side truss rod adjustment thingy is right where the screw would go on the revised neck heel.
I got around this by buying an unfinished body and Vintage Modern Construction neck (doesn't use the side truss rod doo hickey) and cut the body heel myself.