Jason I haven't ever owned a 60 series, so I am just thinking out loud here, but is the extension you are talking about between the transmission and the transfer case? If so, is it effectively the same length as a 5spd with split case? Would that same length of hose work for a 4spd plus extension and split case as well as 5spd and split case?
Last I remember, you probably have a small geography issue and can't measure your rig. Maybe someone with the extension can step up and measure. Thank you for your service to our country.