oil change on my 360

Actually the magnet sits between the holes and just overlaps the holes a little. Secondly it doesn't seal the holes it sits up about a couple of mm over the holes. It doesnt sit flush. I have been doing this since new and oil pressure has never dropped. The motor is well looked after and has not been subjected to race conditions. I have checked the preload on my lifters and none were out of adjustment after almost 7 years. I had 1/2 turn preload put in and 1/2 turn preload they still have. I have feeling that the new intermediate shaft and maybe the distributor could of had some burrs that have worn in There is nothing I can do at the moment. I will just wait and see at the next service. By the way will it be the same if I just put a strong magnet on the sump plug instead?
Regards
Billy D
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