Hey, you forgot the Grid mount

I guess you mean steel spur -not aluminium? Anyway, you don't want it. It is the most scarying and high pitch whine i have ever heard that went straight to my marrow, and that is only from testdriving the car on the floor in my flat. As the steel spur is "stiffer" than the plastic spur it will not seal as good as the plastic spur either.

Do the sanding trick, it is easy and efficient. And get the uprated clear O-ring kit, it has the same part # as the stock, just make sure it has got the clear small output axle ones before you order. The large ones are still black.