The grille shell is a fiberglass 32 and because I am using a suicide front end, I am only using the upper 2/3rds of the grille shell. The aluminum radiator I chose actually turned out to be about 3/4ths of an inch wider which means that the center of the shell needs to be cut and re-glassed so that it will fit the radiator and look good.
In order to use aluminum grille bars, I needed to build some sort of lower mount that would enable the bars to mount and align as well as clear the front spring mount and still look decent. To do this , I made a pattern with a welding rod or you could use a coat hanger, to go from side to side and up and around ( over) the spring mount. Then I transferred the pattern to a piece of 1/8th x 2 inch flat bar and bent it to fit the welding rod pattern. Since I am making this out of fiberglass, I wrapped the flat bar with wax paper and then taped it to a piece of plywood that was covered with wax paper. I then laid up short strips of fiberglass mat - 4 layers total, let set and then trimmed the excess and smoothed it up.
I don’t have a picture to show the next step, but if you look at the picture, notice that there is a flange on the front and then it meets up with the angle piece just made. This piece was made by using the plywood covered with wax paper and laying pieces of mat in the shape of the mount - 4 layers. When cured, I trimmed it to fit the pattern and then used some fiberglass bondo to glue the two together and then used two more layers of mat to bond them into one part. the final shape - from the side - looks like the letter Z.
This picture shows the Z shape with the piece in place with fiberglass bondo holding it. Later on, before I mount the grille bars , I will use some short pieces of mat to make a more substantial bond between the grille and the lower piece just constructed. When it is fully bonded, it will be both rigid, strong, and look good and will hold the bottom of the grille bars in place very nicely.