Finally got around to putting the clutch on yesterday, and pulling the EFI setup off to prepare for carburetifying this engine. The cap screw by the thermostat fought me all afternoon, resisting allen wrenches, vice-grips, and cold chisels until I just got the right-angle grinder and cut the head off. Fortunately, this bolt is not needed on the carb intake manifold.
Less fortunately, there are a couple of coolant passages that do not exist on the carb manifold. I guess it's time for some custom block-off plates, huh?
