Where can we find the ignition switch for the 1978 Dodge Tioga?

Question edited for clarity. 'Manuel' is the name a Spanish gentleman, a 'manual' is the book you need.

There are some good ones in here.

https://www.google.com/search?q=1978+Dodge+Tradesmen+manual

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Hi,

It's located on the left-side of the dash, but behind that left section. If you can't find it, please call dodge directly in order to get a diagram. Their phone number is 1 (800) 423-6343.

Thank you.

check fuses relays and other components for shorts /damage

Should be the same as any 1978 dodge pick up.

You can download a manual for your Tioga from Fleetwood's web site by entering the model and year at this link:
RV Owners Manuals

1978 ,you have no power to the coil with ignition switch on ,if you have power then check it with the ignition switch in start position as sometimes the switch packs up and no power to the coil in start position

Check the wires to the senders for grounding Those gauges have a power lead to gauge then to sender. The more the sending unit "grounds" the higher the gauge reading

Try this: Firing order is 18436572, clockwise.

immobilizer , crank and cam position sensors have not being mentioned
dodge code 32 refers to faulty EGR and not to ignition problems
also if the ignition switch is faulty there will be no run circuit to provide power for the ignition in the run position

here u go.