You connect the DTC to the two 5 pin 240 degree sockets on the 82. Assuming you have the teddy leads (or snaic 5's) then these are the only two sockets they will fit into on the 82 so easy to identify. Top right from the front. You don't use the 4 pin socket between the two.
You connect the 300 to the DTC using the two four pin sockets, which are the only two you have left to use. It doesn't matter which socket on the DTC is connected to which channel of the amp, but it does matter that each channel of the amp is connected by the correct colour coded Din to XLR lead.
Assuming you didn't previously have an SCDR you're about to experience a significant upgrade.