When I contacted Gary at Voice of Music, he advised that I only needed the cartridge and that ordering the kit was unnecessary. I installed a P-228 cart today. I am happy to report that it sounds very nice. There was of course some reduction in volume, but there is still MORE than enough to fill a room with the volume set at about 1/2 full. I am listening to it right now and my wife just asked me to turn it down a little.
Kudos to Gary, he was very helpful, and thanks to pabilo21 for the advice.