DPS went to the fender lettering starting around 1993. Your pics show that at least several vehicles were run as slick-tops with the fender lettering.
Are these '90 models or 93 models without lightbars? Impossible to tell from the pics.
Variations exist, and sometimes agencies put newer decals on cars that were already in service. Here's an example from FHP in the mid-late 90s.
http://www.specialservicemustang.net...P813in1999.jpg
FHP put trunk lettering on the S FL cars. I saw some of these go through the auction, while at the same time, the cars up north, both in-service and at the auction, didn't have these.
My '93 FHP never had these and won't if I ever mark it back up.