I made an X carriage for 8mm rods that will accept a Wades extruder. Have not printed it and assembled it yet, my machine is having fits at the moment. If anyone tries it before i do let me know if it needs any changes.
Looks cool. One thing Realthor and myself have been grappling with making x carriages for the smartrapcore printer (and other corexy's) is that having one bearing less constrained (so open on top for example) makes for a smoother running carriage. But assuming your x rods are very precisely mounted and totally parallel then it doesn't matter.