At William Wynne's hangar, supervised top-end build and test run. Finished installing: Oil pan, starter bracket / ground bar, starter. Filled with oil. Put on test stand and rotated prop for 30 minutes by hand while running oil pump with drill adapter. Installed distributor at correct test run position. Test run commenced about 300pm. Engine started within 2 seconds. Ran at varying RPM for 30 minutes. Adjusted heavy duty oil pump bottom plate to account for slightly stiff rotation to bring it into a level of resistance to rotation that is consistent with other engine builds. Removed from test stand and prepped engine for transport back to Texas.