Bill,
Your picture shows the correct relationship of parts. The carriage bolt goes in from the right, so that it is captured by the square hole in the bumper.


1937 Chevy 1/2 ton
1942 Chevy 1/2 ton
1947 Diamond T Model 509
1951 Chevy 1/2 ton
1950 Chevy COE Model 5700 ~ "Barney" ~ And more pix