Long story short I ended up with two ORO bracket kits to moult a York compressor to the 3.6L JK motor.
https://www.quadratec.com/products/92043_7021.htm
Selling my "spare" kit. Has all the specialised parts (bushes, brackets etc.) but it looks like it's missing a stud (one included to find a match) and a cap screw.
Pulley and belt not included.
Local pickup from Ipswich preferred but happy to post at buyer's cost.
I've got a York fitted to my JK and can confirm the brackets and instructions are perfect - very easy to fit.