NC Cheesehead. To the best of my knowledge the Wisconsin style fish fries have gone over really well here in Colorado.
The Denver restaurant doing a fish fry is called Spanky's Roadhouse. It is located at 1800 East Evans Avenue, Denver,Colorado. Spanky's is right next to the University of Denver. They offer Lake Perch, Walleye or Catfish and serve on Friday and Saturday. I go on Saturdays , as the there has been a long wait to get in on Fridays.
Aso there is another authentic all you can eat Wisconsin style fish fry, north of Denver. It is at Rocky Flats lounge. And their address and phone number is 11229 Highway 93, Boulder, Colorado. 303-499-4242. Rocky Flats also serves Lake Perch, Walleye or Catfish. But they only offer their fish fry on Fridays. I get there early, and there is always a line out the door by the time I leave.
Here is a youtube video of Rocky Flats Lounge. YouTube - Rocky Flats Lounge Walleye Fish Fry