I have just added to the Ford Split Lap Unit 77 page of OnTheDash, and am copying the information here.

The Ford Split Lap Unit 77 chronograph was designed by Ford Rallye Sport (RS) (Germany) and manufactured by Heuer, in 1977. Ford Motorsports wanted to produce a watch that would be the "ultimate" watch of the era -- in terms of both its functions and its design -- and Ford turned to Heuer to produce the watches. The two LCD modules were adapted from Heuer chronographs (the Senator and the Kentucky); the case was a unique design for Ford. Heuer referred to the project as "Project Henry" [a reference to Henry Ford].

The Ford Split Lap Unit 77 watches were sold directly by Ford, at the price of 630 DM (equivalent to $270, on average for 1977). The Ford Split Lap Unit 77 chronographs were made in a limited series of 2,000 watches, and were thought of as the "Mark I" (first edition), of what would become a series of special watches, to be offered every two or three years. Alas, if the Split Lap Unit 77 was the "Mark I" of the series, a Mark II version was never produced. Still, these Split Lap Unit 77 chronographs are cherished by today's collectors, with those pieces that are still operational being especially prized.

To see a copy of the Instruction Booklet for the Ford Split Lap Unit 77, click here.