When we ran a full service chassis fab/turn-key hot rod shop a number of years ago, it was always useful to have threaded things around to weld into the frame for some kind of mount, etc.
Here’s a list of all our threaded things for your reference:
Mustang II Boxing Plate; 47-54/5 Chev PU; Front, EA
Product Details
Brand: Welder Series
MPN: 534720
Country/Region of Manufacture: Canada
Thickness: 3/16"
Front boxing plate for your first series 47-54/5 Chev pickup. Priced individually.
The tabs can be bent with an adjustable wrench along the laser cut slit. These will hold the plates in the frame while you tack them in place.
Note: does not fit a 1 ton truck from the same era.