Gavin's got a very important point here - decide whether this is a cosmetic job or a back-to-bones bare metal job first. Anything other than cosmestic and you could be discovering that the cost of panels, welding and preparation costs you far in excess of the paint job...
...lets face it -once you've stripped back to bare metal you might feel loathed to paint over the rust holes. You 'might' be lucky...
I saw an article in Excellence once with this guys 356 that looked terrible, all cracking paint, the works - but the crux was that the car had bags of character and was mechanically A1 and the business to drive. You could argue that you might get more fun out of 3Ks worth of engine, brakes suspension (etc) tweeking and a weekend on the car with the Zymol and Waxoyl. Just a thought...
SRD