>i was thinking of just nipping down to grossmans and getting 20 feet
>of
>PVC pipe, fittings, and cement and doing it up.
>

DON'T use plain old PVC, Your engine compartment is hot, so's the coolant, 
and its under pressure inside the cooling system. Plastics tend to 'creep', 
they stretch/move under load, and high temperature really speeds up this 
process. The 'load' is the 15 PSI in the cooling system, so the piping will 
balloon out until it gets what are called fish-mouth fissures, whence it 
spews its contents all over. The are miles of buried plastic pipeline for 
natural gas in our western provinces, all of it developing fissures slowly, 
under pressure and at considerably lower temp. than in the boxer motor.
        I don't know how good household plastic hot water pipe would be, but 
remember, your house piping doesn't see water at 200+ fahrenheit for 8-10 
hours at a time! (+ vibration!!) My system is going too, but I'll try to use 
rad/heater hose for the fixups, rubber+canvas not pure PVC. Rubber doesn't 
get brittle at low temp either.    tim smith