Another couple of suggestions would be to call the Service Center in Jackson Center and ask them how they would solve your problem.
Also, given the model number of your existing furnace, you should be able to look up dimensions and configuration. Vendors of new furnaces SHOULD be able to recommend replacement units (there could still be issues)
If you want others to be happy, practice compassion.
If you want to be happy, practice compassion - The Dalai Lama
1984 310 Limited Motorhome
Courtesy Parking (W/S/E/Wi-Fi) on I-5 in Northern California, 70 miles from Oregon border