Lowering A '92 Ford F-150

I sold my buddy my '92 f-150 and he wants to lower it, now i know it has spindles, springs, and i-beams. I thought i knew that you could lower it with either.but when im calling lordco or the local auto parts place, there telling me the only way to go is i-beams. My buddy doesn't want to go with the i-beams, there way more expensive, any thoughts??