Glad you found us! And a great question. It really comes down to demand and R&D time to find, measure and test mount a cover on any given truck bed. The demand is low for Peragon covers to fit the 1987-1996 F-series, so we haven't invested the time to look at the generation before that.

It is possible the generations are quite similar. There are two aspects to consider: 1) the inside length and width (front and back) measured at the top of the bed and 2) the bed lip design for mounting. The dimensions would be pretty easy to compare, where it gets sticky is the mounting. Until our engineering team has had a chance to evaluate the lip design and test fit mounting, we hold off on offering a cover for a truck bed.