I dont put alot of miles but I do put alot of rpm to the MP unit. Only one small hole drilled for maybe a few extra drops of oil, but anyways this is my last inspection/cam change pic, all 3 times ive had to give it a small smack with my palm but never shows lil signs when I take it apart.
I "think" maybe the back tabs maybe just brush the cover which still wouldnt impact its use..but what do I know. I do know I go over 7k alot and this unit shows very little wear, I do pack the gears with red grease when I put it back together for fireup
If mine didnt go on with just a light smack id look more into it, but as mentioned its never showed any signs of anything wrong.