My opinion... the car will never be worth what your thinking of putting into it. So if you like to lose money and the car will be staying for a good amount of time, go for it.

But, with it being registered, by the sounds of it, a good amount of rust, paintwork needed and something dodgy going on with the clutch etc would be too much for myself (How hard was it hit? could it be twisted and causing the clutch to not mount correctly or twist when being driven? 4 clutches in such small amount of miles is ringing alarm bells sadly.

In the long run, it would be better to sell that one for bits etc and buy a good one. Would cost you less in the long run.