Figured I'd post a few pictures since I haven't seen the comparison before. The 14.5's are statistically 2.7" Taller, and 1.3" wider than the 12.5's. Which is a similar jump from the 10.5's to the 12.5's. However, what the specifications can't show is that the 14.5's (and larger) tread pattern starts to flatten out, they have less of a "crown" than the 12.5's.
I will have some mounted photos in the future. You do need a minor cab lift to fit these tires. These are going on my other 404.