I just got a proportioning valve from Ecklers. This is the first time i've seen one of these so I need to know if bought the right one. It's the brass type with the low pressure warning terminal. In the online pictures, on the end that is opposite from the large hex end there is something that looks like a black plastic plug or something, but the valve i got does not have this, it's just solid brass on that end. So my valve has 5 places to hook up lines to total. Is it supposed to have only 5? Can I still use this style?

5 ports, 2 in from master. 2 to front brake lines, 1 to rear line.

The black boot covers the front metering valve stem on a disc/drum system.
Your current valve is a disc/disc valve which has no metering valve inside. The rear nut houses the proportioning valve, and it is set to proportion the rear brakes correctly for whichever disc/disc vehicle it was designed for.

So I guess i can't use it since my car will be front disc and rear drum. I'll have to return it then.