I regards to the hole spacings, if we went with the mounting disc/ring/plate to sandwich the disc to the hub the hole spacing would not matter and any disc replacements in the future would not be a drama.
A while back the issue of wheel spaces came up. It is something that will need addressing as well. Maybe another machined/laser cut plate could be made up to fit, but drill and tap it to take the bolts from the disc mounting. That way it is not just a spacer and may not be considered as such.
If there is a disc that fits over the hub flange I'm sure it would end up so big the rim would not fit. :(
Has the option of hilux calipers been considered? They would be cheaper and if we have strayed from Land Rover parts already a bit more can't hurt ;).

