i pull my vintage trailer with my 40. i drive around 50 mph with it hooked up. with no braking system on the trailer i have had no stopping issues at the speeds i drive. to help assist stopping i added a hydovac, so between that and my 4.56 rear i found no issues yet with that combination. the only thing i have to do is swap out the 12v tailights for 6v. since your truck is so pristine id keep it that way and drive it. take with you the normal spare stuff so you can replace it along the road it need be. if its major breakdown regardless of what you have you'll need a tow anyway. so relax and drive on
an original vintage truck pulling a vintage trailer doesnt get any better than that when traveling. oh not to mention the looks from the passerbys
