The rectangular acrylic piece just snaps right in there. It is a perfect fit. The heatspreader is gripping it all around, and the acrylic piece rests down on the PCB itself when you push it in all the way. The depth from the outside of the hole to the pcb is less than 2mm. I wanted 2mm thick acrylic b/c then it would be almost perfectly flush, but the thinnest standard size is 1/8" (3.175mm). So, that's what thickness mine actually are. It still looks great, though.
Yes it was a little expensive for what it is, but it was sort of a proof of concept. I had an idea, and I wanted to try it...it'd never been done before to my knowledge. I had thought of getting a lot more pieces cut from the same sample, but if that didn't work I'd of been out a bit more money. Plus, I only paid $50 for 2 of those GB's, and $20 for the other 2GB's, so an extra $30 puts the total to $100 for 4GB modded Ballistix Tracers. Bargain!
Suprchargd & I are thinking of making a bunch of these. He has access to some good cutting equipment, but even if he can't cut them accurately enough, the cutting charges where I got mine are not too bad when you get a lot of pieces. It could work out to where these might be available for very cheap. $1/piece or less perhaps. Should be able to send these in just an envelope w/ stamps, so shipping charges will be low.
I'd like to see a show of hands of anybody that may be interested. You won't be frowned upon if you decide not to get them if they become available. If we see enough interest I think we can make this happen.
If this happens I'll start a thread in the classies to sell them.