The 707 will do that without the need for a different Autopilot.

Create a route in the default *FS Flight Planner, save it, click OK to exit the FS Flight Planner, and the route is loaded. When you're ready to track the route, turn the Autopilot Mode Selector knob to NAV (make sure that the Doppler-INS Switch is set to Doppler, but DO NOT turn the Doppler on), and the 707 will happily follow you planned route to the destination.

*You can create a route other ways and as long as it saves them in the default FSX pln format, the 707 will track the route without any problem. I often create routes using FSC 9 (Flight Sim Commander 9.7) and save them to the Documents\Flight Simulator X files folder, and fly them with the 707/