Thanks. The original was 3/16". Which was plenty heavy considering it only holds up tail end of front end. But I Didn't have any 3/16" the right width, was to wide or to narrow.. so used 1/4 instead.
Its coming along nicely. The truck is in remarkable shape for 61 years old. Its got spots of rust, like these fender mounts. Otherwise everything else on frame is great. Body is not bad. One place in driver floor pan and one place on passenger rocker panel. The hard top will probably need the most attention. It appears factory, if not who ever built it did awesome job.
Now have the front frame and cowl painted. The engine is back in and is movable under its own power again.