In reply to Abr:
It'll be fine.
Fumes are very unlikely to be an issue and if it does start to smell a little bit in the car, just drive with the windows open - problem solved.
I once drove around with the entire muffler box and tailpipe section in the boot for a few weeks because it rusted off completely.
At some point a polite man or woman in a spiffing blue uniform will come over for a chat though, so make sure you have your story prepared in advance. Driving while sounding like M1 Abrams is technically illegal.
A garage in Italy once did me one of those baked bean can + gun gum + jubilee clip type temp fixes and it lasted for ages. Like maybe 6 months or more.