Re: Drywall over wall boards???
The way similar situations are handled when removing lath and plaster is to remove everything to bare studs. This is the perfect time to add any additional wiring, plumbing, or insulation. Then fur out the studs so that the finished surface of the drywall will be equal to that of the existing finished wall. That means adding 1/4" shims to the stud, plus 1/2" drywall will give you your 3/4" finished wall.
I suffer from CDO ... Its like OCD, but in alphabetical order, LIKE IT SHOULD BE!!!