heater fittings

I am in the process of making my own heater for my RTV. I'm using a heater core from a saturn and a 12 volt fan from a vent in a travel trailer. What I need to know is what size fittings I need on the engine and the location that these fittings screw or tie into. Any help would be appreciated.

thats gonna be tough. If someone has the heater kit, the parts breakdown should be in there. </P>

Believe you will find a plugged port on the thermostat housing for one hose. The second goes into the bottom radiator hose with a T fitting. Good luck. David/