Here are pictures 275/60x15 good year eagles on 15x8 hweela with 4 1/4 back space. No spacers needed. The quarters on this brown Duster are original and not trimmed at all. I have been using this backspace on these cars for several years.
In the 80's you could only get 4 1/2 back space on several after market wheels . With 4 1/2 they are a lot closer to the leafs and would lightly rub the leafs. We would use 1/8-1/4 spacers back then .
But with these new custom back space wheels from "Wheels Vintique/Summit racing" spacers are no longer needed.
I had a problem with my wheel I ordered from them . It came in and was a 4 1/2 back space I sent it back. Summit contacted me and told me for the wheel I wanted that is a special off set they do not do. I had one of their wheels that came in the trunk of a car I bought. I took pictures with there markings and they made me a wheel to match. It cost me almost twice the cost of the first order. I believe they changed there custom order cost for the better. Make sure you correctly measure them when you recieve them.
Here are some pictures of 4 1/2 wheels of just some of the cars from the past I owned.
I have owned many more cars than these pictured. I never had a problem with them fitting. Buy 4 1/4 You can always space them out. You cannot move them in . As far as stud length. There is a common rule. You only need the depth of the width of the stud plus 1/8 for holding strength . Unless you have cheap china made lugs