

I've soldered everything but the step 8 headers at this point. I still don't understand how to do this step with future linuxcnc/mach3 usage in mind. I'm having a hard time imagining what you are aiming for with this modification. Are you going to connect something to the top of the board on those pins? Then why not just stick male pins down the top of the original headers? I'm most likely talking nonsense here, since I have no clue how this board works or how one would connect it to a breakout board->PC parallel port.
I wish to connect GAUPS to the Arduino to begin with, then possibly breakout board->PC parallel port. And I wish for both options to be as easy as possible to swap between. As you suggested, I tried dry fitting the regular headers that came with the drivers on the board, but I cant see how this would work either. The GAUPS board crashes with the Arduino USB port when I try this. And I would have to solder on top of the GAUPS board? If you could show me with a picture what you mean, that would probably help most. If not you can try to knock it into my thick scull (good luck)

Some feedback on your build instructions:
1.Very nice, I followed it with ease. And I have 0 experience with this stuff.
2.Step 2 : "The 1, 2 and 3 labels will match the 1, 2 and 3 silkscreen labels for the A axis. " I Think this should read Y axis, not A axis?
3.Step 5: You could add "These capacitors have no polarity, you can put them in whichever way you want".I did not know this and since the other kind had a positive and a negative lead, I had to check this before I soldered them on. Might be common knowledge to many, but I learned it today!
4.Step 7: The long ends go up, right? This was pretty obvious once I tried to fit a jumper on them. But It wont hurt to mention it in the text.