thermal heater on a Perkins 2.5l

I need help finding where the thermal heater is we had a friend put in a new ignition and the wire is no longer there for the heat he put in the wrong switch in I have a new one but need to find where the wire goes

The Thermostart is screwed into the intake manifold. Likely centered.

The Thermostart looks like a spark plug and there will be a slender hose delivering fuel to it. The terminal on the side is for the wire from the ignition switch.

If the question is how to power it when you have the wrong ignition switch - the original Old School scheme had a separate push button switch. A horn button mounted on the dash or steering column could be used for this.

I have the right switch but can not find it on the motor. would it on the left, right,front or back? I had a shop replace the switch big mistake they put in the wrong one but now i cant find the heater or its wire !

This links to a Thermostart mounted (and painted over) on somebody's Yanmar - not mine. It is located where the intake from the air cleaner meets the intake manifold. Yours should, in theory, be similar.