not a simple solution but here is an idea:
Use this set of brackets to mount to the engine (you'll have to see if you can get just the brackets and not the compressor:
http://www.ebay.com/itm/Big-Block-Ch...ht_3856wt_1124
add one of these to mount the York compressor to:
http://www.ebay.com/itm/YORK-209-or-...ht_1200wt_1124
Does that make sense?