The 58/59 trucks had a shroud from the factory on V-8 engine equipped
trucks...it's a long tube steel shroud, not very common. It bolts to
the radiator mouting bolts as I recall. There's one on a local 59 that
I've worked on (several years ago).
The 55-59 1 ton trucks with a 235 engine came with a bigger radiator,
which has the 6 tabs to mount the shroud...I have one of these radiators
and shrouds (from a 56) in one of my 59 trucks.
I think the shroud you have is supposed to work with the 1 ton
radiator. You can buy these radiators new, they are called the "heavy
duty" radiator. I seem to remember seeing a shroud like you describe on
a truck at a show.
As an aside, the 55-57 trucks had the radiator support mounted in
differnt places if the truck came with a 6 or 8. The 8 had the radiator
support about 6" further back, and had a filler panel between the
support and the grille surround. The 58-59 trucks all had the radiator
and support at the forward position, and used the long shroud on v-8
59s in AZ
oletrucks is devoted to Chevy and GM trucks built between 1941 and 1959