If you noticed no slipping or flaring of the transmission, try the suggestions below...if you did, it's internal and more than likely, will need to be pulled and repaired.

The shifting on that transmission (722.3?) may be operated by a vacuum modulator valve on the side of the transmission.

Check the vacuum hoses from the modulator valve to the engine to see that they didn't get melted during the heat of your electrical fire.

Also check the wiring to the kick-down solenoid on the transmission.

There may also be a cable that connects from the transmission to the throttle linkage...check that to make sure it hasn't become disconnected.

Hope this helps and that you find your problem...Let us know.

The Tenor Man

__________________
Currently Driving.....
1987 Mercedes Benz 300D Turbo - Daily Driver.
2004 Buick Rendezvous...Smaller than it looks!
2005 Mitsubishi Galant - Not bad for a tin box...Lousey Seats
Past Vehicles.....
1994 Dodge B-250 Van- GAS HOG..Succumbed to rust!
1989 Mercedes Benz 260E - Totaled but no one injured.
1977 Mercedes Benz 240D - Loved it, but SLOWWW! - Succumbed to RUST!
1976 Mercedes Benz 240D - Same as above! -
1975 Mercedes Benz 240D - Same as above!