I did a lot of research when i wanted a box for my (now sold) 67 Camaro. I read a lot of complaints about re-man boxes not having the rt parts put back in them after a rebuild and people sometimes having to go through a few returns until they got the rt box.. I bought a used
“XH” – 1985-1992 Camaro – 12.7:1 ratio (this box was also installed on Z/28’s and other high performance Camaros. It has slightly more steering effort required than the WS box.) I believe this box was used on cars originally equipped with 16” wheels
http://www.camarotech.com/steering.html