I have two extra home stereo speakers lying around, I think they were manufactured in the 80s. Is it a possible/a good idea to convert these into guitar cabs? If so how do I go about it?

Thanks in advance.
Well, there's certainly nothing preventing you from doing it.

Is it a good idea? Well, only if you consider kissing your grandma on the mouth a good idea.

Seriously... A guitar cab is designed for the purpose and does it usually quite well. A home speaker is designed to reproduce a wider range of frequencies, such as 20 Hz to 20 kHz. Give it a go. If it sounds good, then you've started the next trend in guitar amps/cabs. If not, quietly return the speakers to their former purpose and consider visiting grandma this weekend. I hear she likes wet, slobbery kisses.
Disconnect the tweeter and crossover if theyre there. Then try it out!
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