okay i got it. If i can get hold of a T jet lump that'd be a good place to start i have experience in the motor trade but whenever a job gets to the intreresting stage, it gets sent away to specialists :/
Three or five door would the first place to start. A five door will have more weight over the back wheels so depending on your engine choice this may be better for chassis dynamics. If you're sticking to low capacity a heavy five door my not be ideal.
Good luck getting a T-jet for less than £1,000 with the loom and ancillaries you'll need to get it running.
The Punto GT would certainly be a cheaper starting point -- it's an extremely tough old boot of an engine -- but will be getting very old by now. EFI is olde school Bosch. Many have been boogered about with by spotty oiks.
the GT engine is not to be sniffed at at all. Seen many making a reliable 230-250bhp and even right upto 300+ which is mental for a 1.4 8v engine really.
But if you did that the only reason to do it would be cause you have a really really really clean mk1 shell, otherwise just get a GT and go through it with a fine tooth comb and sort everything out.