drop your take out, take the pick up out, and have a look basically you want the pick up of the pump sitting where the old pickup did.
you need to do this in a safe way as it is fuel and electricity.
there may be some welding of brackets needed to hold the pump where it needs to be.
re radiator, if your radiator is fucked, i would suggested not changing it. the stock one copes quite well for most people if its in good condition, and its nice and neat, un like most radiator conversions.