I have seen too much carnage to trust stuffing blocks that are screwed in. I make a few engines to order with my own cases which have a larger inlet and these have stuffers cast in situ. As regards repairing a small hole, I certainly would not weld it and incur distortion. I just apply a few epoxy soaked layers on the back.
My racer has run for many years with a hole patched up at a race meeting with epoxy and a couple of patches cut out of a pair of jeans. Do not make trouble for yourself! Kind Regards
Roger M
