Best Way to Ship a Lip?

[low and slow]

Alright, so here's the deal:

I recently sold a lip that I just had painted for my other car (Mazda3), because I'm a broke ass college kid, and Tallahassee would destroy the damn thing as it is (the car has some suspension work, and it's a pain to try to not scrape, etc). With that said, the guy's payment cleared yesterday, so went over to UPS. Basically, they told me that the lip would cost a shit ton of money, because they measure by LxWxH instead of weight and whatnot, and odds are, it wouldn't make it in one piece. Then, I went over to USPS, but apparently I didn't package it well enough. I easily solved that problem, though, so I'm now thinking of heading over to USPS once again to see.

With that said, what is the best way to ship something like that? I have a feeling that if I, like I said, pack it better, UPS might give me a better shot, but I'm not sure. I need to get it out ASAP, so if you have any suggestions, please post up. I'm going to email the guy who I bought it from originally, too, to see what he says, but I'm almost 100% it was sent via USPS.

Thanks!

Kyle