NO, It wouldn't likely do it. (no cooler, not nearly that much capacity, old anyway)
You might run the mill direct/belt drive off the tractor PTO without the pump on there though.
A D4 7U is rated by CAT at 43 drawbar horsepower and 48 belt horsepower. The rear mounted #41 hydraulic unit puts out 25 GPM and the maximum recommended operating pressure is 800 psi.
According to D4Doug you have the gpm but not the psi required. I also agree that an oil cooler would be necessary. I think most motor drive systems are rated at 2500psi. Sorry!