You made my day!! Thank you all for the research and solutions info!
I built an ignition probe-holding adapter that slides to allow for timing adjustment. It is a 3D printed profile part that traps the sensor. Held on with a six mm wide hose clamp. This is a $3 setup for test purposes.
With this setup I adjusted the static timing to 34* btdc on #1.
first flip and it ran nicely at just 3k rpm!! I have always had to do my start and warm-up at 4.5k rpm with the 54* timing for 4 minutes before it would idle down to 2k minimum.
Now it idles steady at 1.5k rpm and will go down to 1.3k for short periods. This is with a room temp of only 40*f.
throttle response was stronger too. it has a 22x8 prop and revs to 6.5k rpm. ( I have a 24x8 to try later).
If the Morrisminor adapter addresses the crankshaft offsets, I will get that setup asap. If not, I'll build an aluminum adapter for a permanent fix.
I can't wait to fly this setup to see how it translates into pulling power!