@ Gelbster:
As we know there can go a lot wrong when installing or deinstalling a roller bearing.
Plug:
which ims bearing upgrade I definetly go with a machined tube style made of a soft aluminium alloy, because it can't twist and will expand more to seal. Also a soft metal won't hurt the IMS tube.
No holes. You'll have overpressure in the IMS tube. The tube was designed for that, because of the sealed OEM bearing.
Regards
Markus