Brad, 3.9V6 Daks use an AX-15 trans. To get an nv3500, you would need to find a 5.2V8 2wd Dak. The way you tell the difference between the two is AX-15 has bellhousing that unbolts, 3500 is one piece, also AX-15 has 22mm bolt for drain and fill while nv3500 has 17mm allen wrench drain plug.
Dion, If you run a high quality timing set like the Pro Gear we sell, you wont have any issues at all, 500+HP with no issues. The front mounted crank sensor seems like a waste of time since the crank sensor works great as it is, if you want to use magnum on a-833, there is a 134 tooth flywheel with correct reluctor available and a magnum flex plate works on a 904/727.