Mike:
A quick one before I rush out and forget!
Check and test the bottom ball joints in the struts. Another prime cause of wheel shimmy.
Uncle Henry was one of the first to introduce the "Sealed For Life" type ball joint bearings. Of course, Ford didn't tell you how short was the actual service life!
Check the lateral movement as is; then; Nut off and break the taper fit (This is where your big hammer and crowbar come in handy: although, personally, I use an air hammer - saves sweat and knuckles, gaiters and seals
).
Rotate the ball joint taper end 180 degrees and re-assemble.
Test again.
All too often due to poor lubrication, the ball wears a flat on one side and allows significant lateral wiggles.