Thank you 3B and Mike B for your very helpful suggestions! 3B, I don't know how you found these hoses. I spent much time looking for the needed length and fittings, but must not know the right way to search. The fittings on these hoses aren't identical to what I have, but they should work fine as long as the 7/16" x 24 t.p.i. female end fits the male inverted flare on my 1/4" steel brake line. This is probably what was used in my truck, but both the Dorman and Raybestos application notes state that two hoses are used (one on the right and one on the left) which still leaves me wondering about supply capacity. I guess the thing to do is to order one, see if it fits, then cut my original hose to check the inside diameter.
I did check the site recommended by Mike B. It has a very long list of fittings, but the only brake hose they show has the small inside diameter hole. But something else might be available if I call to ask.
At this point, I think I should just get parts that fit, put it all together, then see if the truck stops empty and with a load of gravel.
