Yah, there's actually quite a bit of room in the trunk, even for a convertible. A large suitcase will (barely!) fit, but a couple of medium sized duffles will easily fit, and there is lots of "hidey hole" room around too. You'll be fine I think.
As for the radio, IIRC, there may have been a jack on the lower right side of the faceplate of the radio for a cable to plug in. Don't recall though.
The worst thing about renting that car is you'll be stuck with an automatic. Having a stick is SOOOOOOOOOO much better IMO!
Enjoy, and feel free to post up pics during your stay, and since no one else has chimed in, pics of gf are mandatory!
