To help anyone who is trying to figure this stuff out for the first time I am posting the sketch I made while figuring out the dimensions of my set up. I included the list of the parts used. Almost everyone will have specific variations in their set ups but this may help people figuring this stuff out for the first time.
The driveshaft in my car was almost 1" shorter than what is recommended by Modern Driveline. I'm pretty sure that was the reason I had a vibration at certain speeds under light load. Therefore I ordered a new 4 inch aluminum driveshaft from Modern of the proper length. It just came in so I haven't yet road tested the DYAD but it feels good on the lift so far. I'll follow up with my impressions once I get a few miles on it.