Thanks for the responses. My further research shows this to be a hybrid between the usual Mopar and GM bolt patterns. It needs a bellhousing drilled to accept both this or the usual GM pattern. I found one on ebay, but cannot copy the photo. Challenge du jour is that the bell does not have the bottom flanges that are the rear motor mounts for the 235. Logic suggests an adaptor plate attached to the 235 bell would solve the problem, but what about input shaft length?
BTW the truck is a 3100. As an aside, it has a torque tube drive shaft, but the Factory Assembly manual and shop manual both call for open drive shaft. This has no impact on my plans, but is a little puzzling.
