Guys - My Mk2 breadvan doesnt have a stereo and its driving me up the wall

I've got a Gamma headunit out of my Mk4 Golf and I was wondering whether it would go into the polo? (Sorry about the stoopid questions but I am clueless with this kind of thing!). The Gamma headunit needs some kind of connector but all I have in the polo are some wires - 1 red one, 1 brown one, 1 thicker yellow one (plus aerial and speaker cables).
Any help would be wicked.
Cheers