I have an old (circa 1970's) Delex single handle faucet on my bathtub/shower. Directly under the faucet handle is a chrome push-button assembly that operates the shower diverter. Currently water runs out of both the shower head and the tub spout. I do not know what the design of the converter unit is and I would like to know more information before I tear into it and find that it can't be repaired. Is the shower converter unit easily repairable, as in washer replacement, or does it require replacing a cartridge or something? I would prefer repairing it as opposed to removing tile and replacing the faucet assembly.