1998 Mercury Sable

Hi I'm Jim and I recently rebuilt a push rod 3.0 L sable engine and its running hot!,,the fans work with a hot wire,directly from the battery,,the fuses look to be good,I swapped the relays (Same part #s)aroung in the main fuse box under the hood,while I shorted out the FWD wires (2 prong) by the thermostat with the Key on and nothing?,I'm not sure where the fuseable links are at?,,I believe this might have been the initial problem of the engine/head gasket problems,I had to replace both heads,can someone please point me in another direction?!,,Thanks,,,,,,,,,,,,,,,,,,,,,,,,,,,Jim