WooHoo! another update...
This is looking better
Finally finished mounting and installing the new tires on Maxine today...
A big improvement over the 5.70-8 temporary spares...
Lots of learning, lots of colourful

and days spent testing my patience and persistence

In the year the tires have been sitting in the basement, the sidewalls and tread developed a real attitude problem.
Center of the Tread sank in and the sidewalls followed them - until the sidewalls of the 23-10.50-12 tires were only about 6" apart when mounted on the rims - that left a 2"-3" gap between tire and inside edge of the rim
I tried stretching out the tire by putting an inflated inner tube inside (with an old stock pot to fill the gap in the middle)
- the problem I ran into initially was even though it stretched out with the inner tube, it didn't stay that way long enough to seat the bead...
Good excuse for a new toy from Amazon -

a bright yellow bead blaster...
Took a little practice but eventually got the first tires bead to seat and hold air...
2nd tire - more frustration - just couldn't get the angle right for the blaster to blow the tire onto the rim...
Took the 2nd tire back off the rim, cleaned off all the tire mounting lube, stuck the inner tube back inside and REALLY inflated/stretched out the tire - left it for a few days in the cold basement, and today when I started the game all over again it was also a lot cooler in the BigSky shop 7°C (44°F) instead of the balmy 20°C (68°F) I had when mounting the first tire on the weekend...
Got lucky and the tire kept it's stretched out shape much longer when the rubber was cold and stiff...
It went on and and the bead caught with just a little wiggling of the tires - no bead blaster required
Easy to tell the Amazon Bead Blaster is from offshore - never have I ever had to convert from MPa to PSI -

think it will be getting a new pressure gauge in PSI if I decide to keep it...