MPGVAN, I found this information on a high stall torque converter for your application.

As with the E4OD and A4LD transmissions, few vendors have yet to produce higher stall-speed torque converters for the AOD-E/4R70W transmission. However, Baumann Engineering can provide a custom-built torque converter for these and most other applications. In the case of converter clutch style transmissions, such as the AOD-E/4R70W, E4OD and A4LD, we rarely advocate removing the lockup clutch assembly from the torque converter. Therefore, we provide our converters with new heavy-duty lockup clutch assemblies. This allows you to selectively control converter lockup with the Baumannator TCS™ or even external switches if desired, thereby providing maximum efficiency and versatility with no adverse effect on vehicle performance.

I don't think you need the high stall torque converter, but that clutch lockup assembly sure sounds nice. It sure wouldn't hurt to have a high stall know that I know they are available. Just do a google search for these guys and see if they can help you.