Backhoe Hydraulic return

[TedBellamy]

I want to connect a McConnell digger to a Massey Ferguson 165 industrial tractor (3303-5) I can take the feed from an isolator block on the right hand side of the transmission cover but where can I connect the return pipe? At present I just poke it into the filler hole but this is not a good or permanent solution. Any thoughts welcome.