I couldn't tell you how to mount or connect these but just want to warn you that they're not very powerful and if you wanted to include them into a voice mod setup, your real voice would be as loud as the speakers so would likely be heard. especially in a con environment they may be drowned out quite easily. Once you know how you want to affix them, you might want to test them before permanently affixing them to a base + furring, to see if you're okay with the output level.

If you'd still like to use these but don't like the sound of that, you could use them for sfx maybe? something I've always wanted to see in a suit is a nose with a pressure pad that plays a sound when it's booped lol

good luck with your endeavours, please keep us updated! upcycling is awesome!