Re: speaker question

the woofers that I got are stripped from an old cabinet, so thats all good. What I don't understand is:

Using a store bought 4x12" cab as am example, does this include woofers and tweeters? If so, how come the tweeter is the same size as the woofer? I'm actually having problems finding tweeters made for guitar speakers.

I also looked up the frequency ranges for amps, and I found that they usually don't go higher than 5khz anyway (the woofers I have can go a little past 6khz) so could I still do it with two woofers, taking into account the fact that they come from an old cabinet, and then have an appropriate frequency range?