I don't think the 29 inch depth will be a problem for lights. The standard depth for that size tank is about 25 inches, so you would get about 15% less light at the substrate level with the deeper tank, and that is well within the uncertainty involved anyway.
I would start by looking for something in the neighborhood of 350 to 400 watts of T5 lights, with the ability to either shut down part of the bulbs or raise the light if that proves to be too much light. I think I would consider 3 - 150 watt HQI lights suspended above the tank so they can be raised if necessary to reduce the amount of light, if you prefer that type of light.
The best advice would be from someone who has a tank about that size and has success with a particular light fixture.