I have changed the fuel pump from a lazy manual one to an electric example and spent several hours chasing water leaks around ...the reducer pipe I made had a couple of weepy pinholes in it and some second hand jubilee clips decided to not seal as well as they should ..I ended up replacing the top hose at the radiator , doubled up the jubilee clips on the bottom hose as well as lengthening it a bit and replaced a weakened radiator cap ...but all's good now ...
https://www.youtube.com/watch?v=SSN1Sw22cZM