All those chamfers and radii are gonna kill you!
Like JD says, it's got a lotta missing faces.
Probably translation output settings need to change from the original source.
When I use 'purchase parts', I usually make my own from scratch in Inventor.
That way, they're 'native' and I make them as simple as possible, but with enough detail to make sure it will bolt-up, not have any interferences, and connect to what it connects to (and look like what's in reality)
If this was my job, I would figure out what I absolutely must have, then build it inside inventor. Probably won't take you more than a 1/2 an hour.
OTOH, if you have a Library of these to make, then that's a different story!
... Chris
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