I finally got around to converting the 184 to electronic ignition. I decided to pull the distributor off the tractor for the install. Having worked with distributors before, I rolled the engine to TDC on #1 cylinder and marked the rotor position on the distributor. Also marked a matching line from the distributor body to the tractor.
The points & condenser came out easily and the Pertronix 1442 from Helmar went into the distributor too easily. There seemed to be some slop when I put the rotor onto the shaft above the magnet. It just didn't seem to fit very tightly and some house cleaning found the rotor to be worn.
Put the assembly back on the tractor (lining up the marks) checked the plug wires and then started working on the wiring.
Since this is a 12V negative ground tractor with an internal ballast resistor inside the coil, the wiring was a breeze. Connect the red wire to the key powered side of the coil and connect the black to the other side (where the points were previously connected).
Satisfied with the install, I twisted the key and no fire. Connected the timing light to #1 and the timing light wouldn't flash - no spark.
Set #1 cylinder at TDC again and double checked all my marks. Seemed to be ok. Doesn't seem to be spark on any cylinders so maybe the coil wire got damaged during the removal and reinstall.
After two hours of tinkering and removing distributor again, I realized the magnet was not seated far enough down on the shaft.
Used a socket and a small hammer to seat it down and then noticed that the rotor engaged properly on the shaft.
Reassembled and twisted the key and it fired!
Got busy with the timing light and it is running as good as before. I am not exactly certain that I have the timing exactly on, but it is very close.
I would like to tip my hat to the moron that designed a timing mark on the opposite side of the tractor than the distributor. Good job on that design!