I've got a 2004 double cab with 6.5' bed. It has a 58" opening at the tailgate, it seems like most of the pre-2001 Hawks have a 60" or 64" rear. from what I've read FWC changed the footprint mid-2001 to accommodate more T100's and 1st gen Tundras...
Wish this one would fit my Tundra!
https://boise.craigslist.org/rvs/d/lake-fork-four-wheel-camper-hawk/7229294953.html
1999 Hawk $4,900 fully loaded in Boise (not mine)