On Wed, 21 Dec 2016 08:20:28 -0800 (PST), trader_4 advised:

I'm left wondering why you over inflated the tires to begin with.

That's a good question.
Remember, I'm not an expert (and I never claimed to be one).

Also remember that I am asking for advice, so, I will tell you what I did,
whereas someone else will make believe they did everything perfectly (which
is how all DIYs are written, from a 20/20 hindsight perspective).

The reason I inflated them to 45 was that I had to inflate them to about 60
PSI to ensure the bead was set, and then I dropped the inflation down and
checked the bead with soap and water for bubbles indicating a leak.

As a *further* leak indicator, I set them all to 45psi to see if they
leaked. Since I wasn't going to have the tires for a long time, I was
planning on checking the pressure after a few hours while I had the vehicle
overnight.

My plan was to drop the pressure to 35 when the owner came back for the
vehicle. The owner came back early to pick up the vehicle, so, I just plain
forgot to do that in the fuss, so, I never checked if they were leaking
down from the 45psi.

In the meantime, I did five more tires, as an experiment and for practice,
where I patched each one of them with a home-made plug-patch.

Here's the inside look at the plug:
http://i.cubeupload.com/EJF4y3.jpg
And here's the inside look at the patch over that plug:
http://i.cubeupload.com/OmMamJ.jpg

Of the five experiments, one tire still won't go on the rim, even though we
had a matched set of tires and rims, which went on just fine!
http://i.cubeupload.com/nJNap0.jpg

For the life of us, we can't figure out *how* to get this last tire on the
rim, even though its sister tire and rim went on just fine. (We even bent
the tire iron tip, using all the force that we did.)
http://i.cubeupload.com/OoAABt.jpg