Yamaha DTXpress/DTXplorer/DTXtreme

I haven't seen this on the message board but perhaps it has been 
addressed in the past.

I am attempting to connect one TP65 and one PCY65 to the extra input 
jack ( 9/10 ) which is intended for a PCY65S. 

Hooking them up through a standard dual mono to stereo connector 
results in double triggring due to the signal routing throught the 
opposite pad and triggering both inputs. I previously had two home 
made pads hooked up using a cable with diodes inline on the common 
line to keep the signals separated. I opted for the two yamaha pads 
mostly for looks, but for some functionality as well. The problem I am 
having is in trying to pick the correct diode for the cable, I can't 
seem to make it work with the stock pads. 

So, my question is: Is there a cable available to hook up this 
configuration? If yes can anyone direct me to a place to purchase etc?

Thanks, Peter