58 Hound,cant help you with the 73-87 units.I installed the TCI unit in my 55,and man what a difference in ride and handling. I went with 5 lugs 4 3/4 inch bolt pattern all the way around.Number one reason,there ia a better selection for aftermarket wheels with the 5 bolt.Also I wanted all wheels the same,so I only need to carry one spare tire.Whichever way you decide to go,make sure you maintain the same front axle position.And oh yeah,my truck is used only for cruisins,and shows.
