Hello Star152
Yes, if the used camper you are looking at was not built taller for the Ford SuperDuty trucks (1999 - 2007, F250 & F350's), you WILL need to add a small base to the camper.
I think we usually add around 2" platform so the the cab-over bed on the camper won't be touching the top of your truck cab.
Here are some sample pictures ... the pic with the grey base is one we made for a customer here at FWC, the other pic with the undersized white base is a customer that came in awhile back and I took a picture for my files ...
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