Hi all... so here's an update:
I received my new rotors (aka discs) late this afternoon, and completed the new install (along with new cabin and air filter) and am happy to report that the Zimmermann's worked PERFECTLY! No rubbing, no squeaking, no nothing!
Thank you all for your suggestions and for setting me straight on NOT buying cheap parts. I'll never do that again!
Next on the list is the new top I purchased from topsonline - Robbins German Cloth (black) with glass window.
Please don't tell me I goofed with this purchase as well!? I don't think I'll attempt the install on this one...found a shop that's does Boxsters that's charging $600.
Oh, chrismanchr, the two screws came off easily for me ... all four wheels. I got lucky I guess.
Cheers all!