Quick/Easy Ball Joint Replacement: Without Removing the Axle

(For the Reader's Digest version, go directly to the "SOLUTION" section below.)

The right side ball joint needed to be replaced, so dove into it yesterday. Appeared to be a simple. straight forward procedure.
PROBLEM:
The castle nut that secures the ball joint to the steering knuckle: you can't get a socket wrench on it because there's not enough clearance between it and the CV joint above it. Uncharacteristically bad design, Toyota, but not a huge deal since the Toyota manual calls for removing the axle to change the ball joint, but even with the axle removed, you still can't get a socket on the castle nut because the collar of the hub protrudes over it. (Really bad design, Toyota!)
So the only way to remove this nut, is with an open end wrench. OMHO, an open end wrench is not a tool that should ever need to be used in suspension work. As expected, the wrench couldn't get enough bite, and rounded off two of the six points on the nut.
I needed to apply heat to the castle nut, but with the CV axle directly above it, the rubber boot would be damaged if not protected -- also the tie rod end is nearby, so the rubber boot on that could be damaged if not carful.
SOLUTION:
I grabbed about two feet of aluminum foil from the kitchen. Doubled it over 3 times so I had approximately 6" x 6" square of foil that's 6 layers thick. I then formed the foil into a heat shield/cap over the ball joint to protect the CV boot and the tie rod end boot. See pic. (the pic shows it with the new ball joint installed because I didn't think to snap a photo while I was disassembling.) I was careful to be sure there was an air gap between the foil and the CV joint -- it's OK for the foil to touch the nut and the steering knuckle, but it's imperative that the foil not touch the CV joint.
So I heated the nut with my propane torch with the flame relatively low, checking periodically that the CV joint and tie rod end were not being heated. I was expecting them to get warm, but to my surprise, that didn't happen. The aluminum did such a good job dissipating the heat that the CV and tie rod boots were not even warm to the touch! I heated the nut for about a minute, then put the wrench on a part of the nut that had not been rounded off, and it loosened with very minimal force. Success!
So I could have achieved the same results by removing the axle, but this easy solution saves that step -- and a fair bit of time & hastle.