This is an OPS40 engine, I used a Octura Hummdinger insert and 1/2" Delrin square bar stock, 1/2" Delrin tube, 1 washer, CMDi grommets and 1/4"-20 nylon screws. The reason the hummdinger insert was used is because this engine has the crank side bolted on and was told this would be good for strength purposes.
