My '46 PU, running 1961 261 with 46 bell housing with adaptor to T-5 trans. Can swap 216 front mounting plate if you want or drill it to match. Most importantly is the 261 water pump will not clear the radiator, I'll attach a link to an adaptor plate that solves that problem. 261s of your year have LARGE 1/2" oil line and divertor pin that directs the oil. This is a major issue as if you get it wrong you will burn up your engine. If the plug is OUT you can run without a filter, make sure you get this correct. I'll attach a photo of the side of a 261 and the adaptor for the water pump set up.
