Yes, that year and model of MC should have the residual valve in the rear port. We bought one about 1 year ago that had it. If you look into the port on the MC that feeds the rear system (which will be the front port on the MC itself), you should see a shiny, cone shaped disc with a small hole in the center. That is the residual valve (or the retainer for the spring for the residual valve). You should not see one in the MC port for the front system.
You just remove this disc and anything behind it and, voila, no more residual valve in the rear system.
Here is a thread with an illustration of a dual drum MC with the residual valves shown in each port.
using drum MC on front disc setup
