Are you sure you're missing the PTO? It's hard to see from above, as it sits down low, between the hydraulic torus fan drive and the engine block on the driver's side of the powertrain. Almost have to crawl underneath to see it.
You could hang a compressor off the engine, about the only place to drive it would be the cam pulley on the 8V.
Another possibility, many of the V-730s came with a PTO that was used for various reasons - A/C compressor, additional alternator, etc. If you used one of these, the compressor basically ends up sitting on top of the transmission. Geoff's RTS is configured this way, maybe he'll post a pic for you.
FWIW & HTH. . .