The Affinity Strat bodies are thinner than a standard Strat body be it a Squier, MIM, MIC, or American. That does cause a problem with the trem block protruding from the back of the guitar.
I put a std. steel block trem in one of these bodies for someone once, but I had to take down the block about 1/8" or so to make it fit with the trem cover on. That left the string ends flush with the bottom of the trem block, but it worked!
If you're on a strict budget here, this humbucker gets great reviews from everyone who tries it. As I've been told by the happy users, don't let the cheap price fool you.
http://pickersparts.auctivacommerce....er-P95880.aspx
OOPS!- just noticed, you need a single coil size pickup...never mind....
Ah, nothing relieves the discomfort of GAS pains like the sound of the UPS truck rumbling down your street. It's like the musician's Beano.