The tool for mounting tires that I've had forever but just realized its best use is my el-cheapo truing stand with its flat bar construction and feet. Bolt my wheel in with the tire also running through the stand. Start with the valve at 6 o'clock. Grab the tire with each hand about 14" away from the valve. Standing on the stand's feet, I pull outward and up. When that first 10" or so are well centered and stuck, I do the same with the next portion. Final is the usual struggle but even there, the stand and being able to pull up hard makes it easier. And best part? That pulling is done with some of your body's strongest muscles.

My other trick is about 2 feet of 2x4 clamped in a bench vise. I lay the top of the inside-out tubular tread down on the 2x4, hanging down both ends. Glue tape, move 2 feet and repeat. With these two tricks, mounting has never been easier.

Oh, pre-stretching - need varies a lot by tire model and manufacturer. Some require it, others don't. Even the ones I don't pre-stretch, I mount on a dry rim before gluing to get a feel for how hard that tire needs to be stretched. Too much stretch or tool little for the first portion of the mount makes for a tire with larger and smaller diameters. (The fabric doesn't stretch much, it mostly just necks down.)