i am doing the same thing. im restoring a 1970 and putting late style doors on. as far as the door sill. it is the same . as far as the striker goes it will have to be moved in like a half inch to line up with the rest of the truck correctly.
any ways from there you will have to figure out a solution for the door stops, unless the new style stops fit the old style opening. i don't know. maybe someone else on here can tell you for sure. I haven't done mine yet but im looking to do it right. hope it makes sense. good luck