There used to be one in the Milford / Brighton area years ago on 462.675 - 141.3PL.
I dont know if its even still up or not. I "think" it was up on the hill on Kensington Rd, North of 96, but one of the towers up there that had great coverage has been stripped of all equipment 3 years ago.
I will have one up in the Midland / Saginaw area, in the spring. Ive got a few tower sites Im getting access to after Thanksgiving, but wont have GMRS up till after the snow is gone.