I agree with DaveDog the crossover is probably already shot. Or a previous owner may have trashed it. Some have internal fuses.
There's no way to tell what failed when. But I can guarantee you that if you power the horn/tweeter without a crossover the horn's going to fry as well. It may not happen at low volume right away, but it will happen.
(I don't care what some Peavey "technician" told you on the phone)
it has less to do with power than the distance the voice-coil is capable of traveling.
EDIT* re-read DaveDog's reply regarding piezos. I had not considered the possibility of it being a pseudo tweeter, such as piezo. Because I can't for the life of me imagine why such a cabinet would ever be any more useful bi-amped. But that is one explanation that would keep the tweeter from scattering.
However, curious enough to download the PV SP 5-Ti manual which states the horn is a 2" compression driver. And if that's what you have I stand by my original assertion that it will not tolerate being run full-range for very long.
Anyway, believe me - don't believe me. Do it however you want, I'm just trying to save you some repairs.