As they say moments of idiocy are sometimes followed by a flash of genius

! After my "wrong shocks" moment earlier I came up with a great idea for the spacers.
So I had this really fancy bit of aluminum that was basically useless, until I noticed it had a really nice cutout in it that matched the bottom of the shocker perfectly..

I think you can already see where this is going.. So I threw it in the strut and the clearance was pretty good.. only about .5 of a mm all the way around..
And chucked the insert in and tightened it down...
A perfect spacer! It sits down in the bottom well and the shock fits in the recess and is supported nicely - job done!