I rebuilt my 54 235 about 10 years ago. They replaced the seats, valves, guides, etc. I have not had any problems. The new seats are harder and allow the use of unleaded fuel. The expense for doing it right the first time is much less than reworking,in a few years. At least, my opinion. Make sure you have a good shop, talk to the hot rodders, they usually know the good shops. They also know the best price.
