I have mounted and dismounted at least 100 tires at my house with a high lift jack, the weight of my F250, two small tire spoons and a long pry bar. It is 100% safe as long as you respect the high lift jack! I have done everything from wheelbarrow tires up to 40" Gumbo Monster Mudders.
The two tricks are to get the bottom of the jack as far between the wheel and tire as you can, and use the heaviest vehicle you have. Sometimes you have to work your way around the bead too, just depends on the wheel. Once you have some pressure and the bead is starting to go, you can jump on the tire to break it loose.