I have 2 sets of hoses coming off my 186 for the heater. One set from the passenger side of the thermostat housing which only goes to the inlet manifold heater (do we really need this in Australia?) and a second set, one from the spigot on the water pump which is an optional drill out and one from the drivers side of the thermostat housing. I run LPG so this line also runs the gas. Yet some Holden motors I've seen have the one line which goes in a circuit to one then the other, they then have a gauge sender in the hole currently filled by a water hose fitting in the thermo housing.

Is there a more efficient way to do it? Can I do away with the manifold heating or can this cause the thing to ice up running the gas?

The motor is from an HR I believe (186A engine number) but is in a landrover so has been set up differently.

So the lines going to the manifold heater are correct coming from the passenger side of the thermostat housing? Does it make a difference whether the other is from the head or the thermostat housing? How should the converter be plumbed in? I'm pretty sure it is plumbed in with the manifold heater, as done when the conversion was done. Hoping this is correct. I have seen the heater and manifold all in one circuit too, is this another option or someone's dodgy work? I'm just looking for a space to mount a water temp gauge and also a thermo switch for thermo fans, suppliers say the best spot for the thermo fan switch is the top of the thermostat housing but I'd either need to tap a hole to accept it or buy the type with the hole in it from the toranas.