I called Jeep today on mine-I never got a letter. They set up a "dummy" apointment and according to the service advisor will order the kit in and call me when it arrives.
I'm not holding my breath.
1995 Grand Cherokee ZJ 4X4 4.0L Auto K&N FIPK, cat back exhaust, 2" BB, JKS adjustable track bars F&R, 31X10.50x15 BFG'S
1993 F-250XLT 4X4 7.3L, Banks, 5 Speed, 4.10