just did the gauge swap from dummy lights to the gauges. Once the new sending units are in do the existing wires plug right in? Also i am confused about which one is the temp unit. There is a wire plugged into the thermostat housing and the is a wire on the driver side head between the manifold. So which one is which? The engine code is H.....LG4 i believe. Thanks.

 

thermo housing is for the ECM - driver side head unit is for guage

 

thanks. but will the existing wire plug into the new sending unit?

 

guage uses a sender with a single wire