TwinPlenum, whatever you do, DON'T sell your Paprika P6! Sell your soul to the devil/children for medical experiements/organs for transplantation, whatever, but don't dispose of that car! In my humble opinion you've put together just about the perfect 'fast road' P6 (in considerably less time than it is taking me to realise my very similar ambition), a real eye-catcher, and surely a more satisfying car to zoom about in than even the hottest Mini, and I've hurtled around some winding country lanes in fire-breathing rally-prepped Coopers too. Please wait (but without holding your breath) until I've got my project car back on the road, I was actually really looking forward to a return trip back to my London roots and a drag race between your 3.9 TP EFi and my twist on the '3500S with a difference' theme...
Pilkie's right, you could shoehorn a V8 in a Mini, there's one on YouTube that looks really scary, great power-to-weight ratio. There's a red roof-chopped blown V8 mini panelvan out thre too...