Air cooled to water cooled peugeot vivacity

Can I change a air cooled engine into a water cooled engine as my mate is selling me all water cooled parts from a speedfight W/C engine for £50 this includes barrel and head no piston, radiator Nd expansion tank with hose pipes and stator, all I need to get is the pump and gasket set, will the standered ac piston fit the ac barrel, and would the parts fit on my ac engine

 

The main issue on vivacitys is where you gonna put the rad?

Also if your rebuilding to a liquid cooled you'll be better buying a new piston.

 

i was either going to putit behind the front wheel and customise the panel or put it where there normall located on a speed fight or aerox

 

Yeah. You won't be able to put in the front panel as there's no grill on the front panel.