WoW Now thats Excellent to see Xion, very nice.
I know you have thought of this, but I can't help myself.
Drilling the hole in the perspex now in an excellent idea.
I am guess (hoping) that you are only going to bolt the perspex on.
If you do plan to pop rivet it on make sure you use washers on top of the perspex and Don't do it before it's powdercoated.

I know your not simple, it's just that I have seen a lot of really dumd things in fab work before, some of the dumdest have been by me.
Yeah I know you learn from your mistakes.