I'm by no means an expert...But...
I'm guessing you could probably find a company number in all that mess and call them to see if it'll fit your '99. If all else fails I guess you could bid on it and if it dont fit, I guess we'll see it on E-Bay again (Slightly used). I would imagine that it would, if anything maybe a snugger (is that a word?) or looser fit than you would like with the other engine components around it. I don't think the engine compartment changed too much between 1999 and the starting year of that model 2001. But I'm thinking abit pessimistically, if it did "fit" the 1999 model why didn't they list it as such or maybe company just trying to make more money on a "new" version of thier stuff. In short (sorry, I meant to give you the "Reader Digest" version), I would just try to contact company first, anyway... Or just e-mail the guy and see if he knows, if he wants your business, he WILL find out for you