Pictured above is a comparison of Model A and B Ford radiator splash shield bolts (studs), also used for attaching the front bumper brackets to the frame. The bolts in this pic are originals which have been bead blasted and cadmium plated. The cadmium plating is not correct for original finish, which was raven, I believe.
These fasteners are threaded on each end. They have an external fine thread pitch on the frame side, and an internal 1/4-28 pitch fine thread on the splash apron end.
Note that the splash apron screws used are the unusual 1/4-28 fine thread size, not the industry-common 1/4-20 size. Use the correct screw so as to not damage the mating threads.
On the left is B-17766, the front stud fastener used on the 1932 Model B. Next is the front stud fastener A-17766 used on the 1930-31 Model A. The third stud fastener pictured is number A-17767, the rear stud used on the 1930-31 Model A.
The fourth stud fastener is a variation of A-17767 and has a hex-shaped bolt head rather than the common square head style.