As most of you know, the advertisements of the Speedmaster up until 1969/1970 were mostly about car racing, car rallying, sports and the likes. It is therefore no surprise that at some point, a car rallye club - more precisely the Automovil Club Peruano - ordered 50 customized Speedmasters with "A.C.P." on the dial.
It was the only time that Omega customized a Speedmaster dial in the factory at a commercial clients' request
(the "Meister" and "Tiffany" dials were customized by Meister and Tiffany, not by Omega). All 50 A.C.P. Speedmasters were delivered in one batch on July 2nd, 1964.
Cheers, HSTE