We have to keep in mind L&L's raison d'etre.
460 swaps into trucks that didn't come with them.
Unique mounts, flywheels and oil adapters that allow these things to be done more easily in a Windsor based truck.
I've said before they need to make refinements to their jigs in order to avoid the problems you've pointed out.
My personal experience is that everything is solid and good quality.
I'd imagine if you were using their swap mounts (that set the engine a little higher) you wouldn't be rubbing the frame.
(I don't know what this would mean for the radiator shroud)
Jim,
Lil'Red is a '87 F250 HD, 4.10's, 1356 4x4, Zf-5, 3G, PMGR, Saginaw PS, desmogged with a Holley 80508 and Performer intake.
Too much other stuff to mention.