Originally Posted by Al_Alguire
I have always used the RJ kit on both gutted steel and glass doors. Never and issue with it but make sure you go into a stud for the latch..

https://quartermax.com/door-hanger-kit/



one could always use some 1/4"x2" or 3" [or whatever width needed to weld on a spare set of hinge plates and latch mechanism] strap steel to span between studs if the door is shorter than the stud spacing would allow all parts of the door mounting mechanism to attach to.
beer