saddle fit HELP

[TddWil@aol.com]

OK, I've been thru this before with another horse so I didn't think I was a 
total idiot when it came to saddle fit, but...   I got a wintec all purpose 
with the changeable gullet, and ALL the gullet plates. The horse appeared to 
be narrower than my other one that took a medium, so I went narrower. White 
hairs and the saddle kept sliding forward. So we went wider. No luck. So then 
I bent a piece of wire over his back and made a cardboard template to test 
the saddle with. it fit with the widest gullet plate. So I used it on a 30 
mile CTR (last 10 on foot, lame) and he had no dry spots or pressure lumps, 
and I checked him repeatedly that day and the next day. So after a few weeks 
off we did 20 mi yesterday. He had dry spots and a lump on either side of the 
withers. He lost hair on the white spot on the left side of his withers. 
OUCH. The saddle sits a bit low in front but has adequate wither clearance. I 
pulled it back away from his shoulders. I'm using a wool felt pad. The girth 
is not over tight. He is an egyptian bred arab, pretty average conformation, 
he is not rump high. I am about ready to buy a bareback pad and throw a bunch 
of saddles in my front yard and have a bonfire!  

                                                       Shelly