Well I finally found a set of Ford OEM 20 inch platinum wheels and bridgestone 275/55/20 tires. New take offs from the Ford dealer. I think they ride better than my 17s and I got another 1-1.25 inches of height. Here are some pics.
Looks great. Love that first photo, it almost looks like the upper paint in that of a light metallic lavender with a silver lower paint accent...that would have been a great paint option for Ford to have offered. Except we know, real trucks aren't painted lavender...right?
Interesting that you say it feels like it may ride better with the 20" setup. I was kind of wondering if my FX4 may ride better with the 18" tires and wheels give the taller tire sidewall to help absorb road imperfections. The taller sidewalls of the 18" would also be of benefit in off road conditions due to flex and ability to dig deeper into soft surfaces.
On Edit: Ford did offer a light metallic lavender paint back in the late 90s as I recall.