I just bought a 1977 Pontiac Bonaville Heater Core for my upcomming water cooling project. I heard this is one of the "best" heater core to use as it is only ~$20.00 at Autozone. Anyway, how would I go about modifying it to be use with 1/2" tygon tubing? The heater core factory inlet is 5/8" and outlet is 3/4". What parts do I need to make/modify it to fit a 1/2" tubing? Please help a newbie...