Tire mouting problems

[sciroccos at earthlink.net (Jim Ruffi)]

I went to my friend's shop to mount my new tires on my new wheels the other
day.  He has a 20 year old Snap-On wheel machine.  Not state-of-the-art, but
it has proven itself through hundreds of mountings and dismountings.  We
couldn't get the tires on the rims....it was as though they were too tight.

So, I grabbed up the stuff and headed to the tire department of the local
wholesale club.  They are always nice there and do lots of low-profile tires
on big rims, plus their equipment is new.  The guy was perplexed.  He
couldn't get the tire to reach around the rim.  It's as though the rim was a
15 1/2 and the tire was a 15"

Here's what I think.  The rims (ATS) cups have a very deep outer lip.  When
you work the second half of a tire onto the rim, it's necessary to get the
tire to slip into the narrower (diameter) part of the rim, just inside the
are where the bead makes contact.  Only these rims have such a wide lip,
that it's nearly impossible to push the tire into the narrow area.  It would
make more sense to put the wheels face-down in the tire machine and stretch
the back of the tire last....but I'm worried about the tire machine messing
up the paint on the wheels.

Tires are EV100, 195/50-15

Make sense???
Thanks.

Jim