I liked the idea of Edward Niedziejko's linear adaption, but felt there was work still to do on the design.

I've removed some components off the bracket I didn't feel I needed for what I wanted to do with my Hypercube.

This is still in a stage of creation, and I'm currently waiting for a 500mm rail (the 450mm rail I ordered wasn't quite large enough) so I'ts not tested yet.

I extended the bracket to allow both sets of screws to be used to mount ot the Linear rail with 3mm screws.
I dropped the X endstop down in height and depth so that the cables could fit without rubbing on the rail, and I didn't need to butcher the switch PCB.
I also noticed that the X Endstop switch didn't make contact with the XY Bracket, so I've made a little bracket to make this work.
I'll put some photos up of the complete build when it's done, but you'll have to just put up with the test photos for now.

I've allowed for 3mm Nylock nuts in most cases (that was fun to learn).

Note, I have not altered the XY Joiners as yet, but if Edward maked the files avaiable I'd be happy to move the bracket into the model. I may even just rebuild the model from scratch, but Edward has done a very nice job in making them look nice.

UPDATE
I have modified the rail adaptor to allow the cable for the X endstop to pass through without having to go over the rail - so no wires rubbing on the rail.

Hypercube

No

Yes

25-50

Infill is up to you, but I went for 50% for strength.
Supports are handy for the captive nuts.