beg to differ Joe - that TIP is from the factory hood support on Jim Proffit's truck, and seeing it now I recall him talking of it - too bad he doesn't post here anymore, but Randy may be able to add something
note it states "from all indications the hood prop shown may have been a factory item..." and it's identical to every one I've seen on a Deco truck that has one, CDN and US, never seen any other style - if there was an aftermarket for such there would be any number of different configurations, as is the case with all "better mouse traps" - note also that when closed it lays flat against the cowl and at no time would it interfere with anything under the hood
you'd hafta come up with some real factory info to back up the opinion that GM would have made a hood like that with no way to support it when open other than those rubber corners, which I doubt were intended for a support, but more likely just to prevent scratches, just like the early Ford trucks that have the same rubber corner on the butterfly hoods
I really can't believe the N Dakota farmer that was the original and only previous owner of my 46 would have wasted any extra cash on something like add-on hood supports!
Bill