I also just bought a Ranger 33. I bought it at Lake Mead and went through the hassle of shipping it to San Diego. The cost of shipping and necessary upgrades exceeded the cost of the boat, but the final product is going to suit me well.
The boat only has a Porta-Potty, and the remnants of and old macerator system. I want to put in a real head with Y-valve and holding tank, but can't figure out where to put everything. One of the other R-33s I looked at had a flexible holding tank in the forward salon lower compartment port side, but the thing sat over the speed and depth transducers, making them inaccessible. That to me is unsat.