You will weaken the iron drum by boring oversize and shrinking in a sleeve What happens is you end up with two distinct pieces of iron bound only by the friction of a shrink fit. The outer shell, which is supposed to have the majority of the inherent strength of the drum only has a percentage of the original while the liner which is only a shell, maybe is only .063 thich is left with some other percentage which is additive but not back to the original 100%. My guess is that you would end up belling the outer side of the original shell with a continual heating and cooling and losing the integity (fit) of the inner shell to the original thinned drum. But with that said - if it's going to be used on a much lower weight car/rod, probably not a problem. If its going back on a land yacht like the big old Continentals, I would not consider using this arrangement as they needed all the brake possible.
I wouldn't worry about redrilling the inner section- it wouldn't be a problem as it is steel rather than iron and the hub carries the load - you can also carefully plug weld this steel part but probably not worth the effort. also, you can consider elongating the holes - again, the fit is normally the hub.
Then, there is the tried and true Buick drum - finned aluminum 'heat sink' with an iron braking surface - two piece, but designed that way with plenty of stength for the big cars.
I think what I'd do is find a rear drum that would match the diameter and width of the existing fronts and adapt - the old Lincs were big and some of the recent pickups had rears that would probably match - but you would have to find a spec sheet of aftermarket parts to match and fit and a machine shop to do some fitup work. :sweat:
Dave
