Mike,
Wish you could pack up your tools and jump in to help on this project. Another has told me the cab is a Dodge so from now on I better call it a Franken Truck. The history on it is it was bought and taken to a gold mining operation and never registered for highway use. I definitely had a 4 cylinder because there is no room for an inline six engine. When we got it there was a 216 Chevy that stuck through a hole in the firewall back into the cab. The driver was tough because the foot feed was up against the side of the exhaust manifold. The dump lever rods, pto shaft, and torquetube/driveshaft had all been shortened to accommodate the six cylinder. Has a 153ci four cylinder (Chevy II, Mercury Marine) engine in it now that fits both the firewall and the fan to radiator very well.
