you'll have to get a 36 hole rim if you plan on re-using your hubs. On the other hand, you can just buy a whole new 32 hole wheelset if you so choose. Unless you're going to build the wheels yourself, you may end up paying more buying a 36 hole rim and spokes and taking it to someone to have it built than you would pay if you were to just buy a whole new pre-built wheelset.