Many thanks to Tommy Tyler (listed author of the "Simple Interface" and the "6PinConnector" howto guides), and everyone else who makes this group possible!
I have now successfully made my JP1 interface!
After a bit of putzing around (see my post re:soldering), I found the trick for me personally was to use a 25pin connector that comes with the pins seperate. I was unable to solder the necessary wires to the pins when they were in the 'holder' (not the hood, but the small piece that holds the pins...). I found RadioShack piece number 276-1429 to be my life saver!
(http://www.radioshack.com/product.asp?c ... 276%2D1429 or http://tinyurl.com/qepe)Now, I have downloaded the memory from both my Kenwood RC-R0720 and my RadioShack 15-2117! I have also programmed some new macros in my 2117. It's so awesome! Woohoo!