Here are the pics of the converter with crank adapter and flex plate. The crank adapter is machined to accept the 2004R converter pilot, it fits snug. In the pics you can see the spacers between the flex plate and the converter bosses. When I assemble these three parts off the engine I can simulate the actual amount of engagement between the converter pilot and the crank adapter. Once assembled with the TCI spacers the converter pilot goes into the crank adapter pilot hole about 3/16". That should be plenty of engagement to ensure proper alignment of the parts. If I needed more engagement of the converter pilot I could make a 1/16" spacer to put between the crank adapter and the flex plate effectively moving the crank adapter towards the rear and making it engage the converter boss more without affecting any of the other components.
In the last pic you can see the slots in the converter nose. These holes engage the pump inside the tranny, if you pull the converter too far forward when bolting to the flex plate you can accidently disengage the slots from the pump. I believe the Mopar converter is very similar. If there is no clearance at all before you pull the converter forward then you run the risk of the flex plate flexing toward the rear and forcing the nose of the converter into the pump in a way that could damage components. At least that's what everything I've read tells me. Again, I'm not an expert but I do have a few books on the 700R4.
Treblig