Online Community of Zenith Builders and Flyers
Louis according to Elijah's profile it is probably a 750.
The "Option Package Drawings" is a priced option which includes the drawings for the map box. The package is $125 and can be found here: http://www.zenithair.com/cgi/kit/kit.cgi?order=1----STOL+CH+750+Dra... which includes all of the options. They (each option) used to be sold individually for $25 but not sure if ZAC still does that. Probably worth calling them.
Usually if you buy an "option" it comes with the plans. I bought the option package when I thought I would scratch build, but then when I decided to order the kit and picked certain options, those options came with a set of plans for that option. I'm assuming if you bought the map box option kit, the plans should have come with it?