Going to get the burn victim back on the road starting this week.
Here is what happened, according to my forensic investigation:
Transmission oil cooler line had failed via chafe wear thru causing pinhole leak. Pinhole spraying on hot exhaust pipe catalytic converter. Normal driving it would just burn off as air passed over hot exhaust, so no evidence of failure under normal driving.
Emissions test involved two minute engine 2500RPM rev test in park. Flunked first one so they did a second chance test. That's at least 4 minutes of transmission fluid squirting on the catalytic converter with no cooling air blowing the stuff away as it burned on the hot pipe. Sooo, moments after pulling out of the emissions station, the accumulated oil burst into flames. I'm sure it was at least doing a pretty good smolder while at the test facility. Panic ensued.
The major damage was to the engine wiring harness. Thankfully I have the parts truck at the barn, so I harvested the engine harness from that and will need only do a little bit of restoration work to the tunnel area. Not as bad as I had thought although not pretty in any sense. I think what really flared up was the oil soaked firewall pad.
1966 109 5 door wagon 300Tdi "spermaceti fueled"
1994 RRC LeWiB "ruining the air behind me"
All my troubles are Rover