My '54 235 ring gear is sharp, starter is grinding about every 3-4th start. Question is how hard is it to change out the gear, I have 2-good flywheels in my stash, not sure if they are correct for my clutch (both are 139 teeth). How much heat, any pre-cautions? I will take the opportunity to complete the change in transmission/driveline to the open '54 version I have. Just getting ready for the first major retrofit since my restoration, want to make sure of options on the ring gear.