saddle wedge stabilizing

["The Vervaet's" <VervaetP@deruyter.k12.ny.us>]

VervaetP@deruyter.K12.NY.US
After reading the Trail Blazer article about saddle fit...I realized I
needed some "wedges" in the front, for my high withered horse.  I made them
from closed cell foam (as they suggested) and they seem to work great (even
sweat pattern now!) but......how do you keep them from sliding around?  I
put down a saddle blanket, then the saddle pad, then the foam pieces,
finally saddle on top....but they seem to slip around a little when we're
riding.  Any ideas?
Paula