That's impossible to tell from a distance - none of us has an IDE64. However, you can measure: Two corner pins of the clock port are GND, and they are visibly connected on the RR-Net MK3. You can measure continuity on these pins, and you should also be able to measure continuity on these pins on the IDE64 - this will tell you which way round the unit needs to go.
I'll ask soci and add the info to the wiki...
his answer:
No problem. It's on page 236:
https://singularcrew.hu/idedos/IDE64_users_guide.pdf
No problem. It's on page 236:
...with the good old error that someone believes that a clock port has a pin#1. In reality, numbering starts at 19, and it ends at 40. Pins#19 and #39 are GND.
That picture only shows the RR-Net MK2 shape. The MK3 version is slightly bigger and may conflict with the C64 case if connected the right way round.
