dac69er
Super Moderator
The problem with the main caps are that they seat with four surfaces.
When the cap sits loose on the vertical mating surfaces on the block then it can not be used.
If it sits tight or is to big you can carry on with machining.
The use of over size thrust washers may be compulsory if machining has been done to fit different caps.
re machining the caps would not affect the thrust bearing size