Steve, the flexplate is a little lighter then stock i think, i should weigh them and compare the differences. I tried to keep parts heavy on that end for inertia. Every diesel i've ever worked on seems to have really heavy flywheels and flexplates. Probably to deal with all the torque.
The one i designed is made from 1/4" stock. I made all the parts so they could be cut on a laser CNC or High Def. Water Jet machine. That way I could keep the cost low for a kit for others to purchase. I'm not sure if it will sell well or not, but atleast i know it is designed well and fits great. I would never trust myself to make something like this by hand. The measurements had to be perfect, i don't want any weird engine vibrations while its running. I'm very happy with how they came out.