Back in the early 1960's, I watched my boss change rods on a 216 from the bottom side. There was enough room to pull the piston down in the block far enough to slide the wrist pin out of the piston from the crankcase side. I think the 235 is just enough bigger on the bore size to make that procedure impossible, but it won't hurt to try. The rope seal will form itself to the crankshaft flange pretty quickly, so it might not be necessary to go to the lip seal. A rope seal is a lot more forgiving of slight roughness on the crank hub that a lip seal won't tolerate, also.
Jerry
