My house was built in 1986. I am in the process of remodelling my bathroom part of which entailed pulling down wall tile and the wall board it was attached to. I bought some 1/2 inch wall board to replace what I pulled down. When I installed the first piece I noticed that it did not align properly with the existing, abutting wall board. Apparently the existing wall board is 5/8 inch and not 1/2 as I thought. I am not sure how to proceed. I would hate to have to junk the sheetrock I have already bought and I am not even sure I can get 5/8 wall board. I am sure as heck not going to pull down and replace all the existing wallbard on the rest of the bathroom to make it all uniform. It occurred to me to find some type of panels that are 1/8 inch thick and cut strips to attach to the studs before installing the 1/2 inch wall board, but I am not sure if or where I can get anything.

Can anyone help me out there please? Thanks.