Geometry lowering spacer

Hi,

I've made a lowering spacer for my cartridge fork. But I'm wondering if it isn't restricting the oil flow.
This are the internal parts, Showa CR125 '93:

The top cap screws in and the rebound spring is locked between the cap and clip.
The elliptical part above the shim stack is smaller than the clip, so hits the spring at the end of the rebound stroke.

Now the 1 inch spacer inbetween has 1mm clearance between both shaft and tube. So the tube is 25mm ID, the spacer 24mm OD. And the hole in the spacer is 13mm, with the cartridge shaft being 12mm. I cannot make the OD smaller, the spacer would slide into the rebound spring. I could also swap the rebound spring and spacer, the lengths are equal, but then the steel spring iwill be sliding against the alloy cartridge tube all the time

My question is: does this spacer restrict the oil flow?
If so, what would be the best alternative/solution?

Thanks!