Hey there 57
Honestly, if your looking for temporary "seats" for the family/friends in parades here is my idea..
If you place seats in the back up against the cab of the truck you can get 2 MaAAAAAaaybe 3 people to fit there. Beings your truck is a short bed, I would place 2 benches (one on either side) that run the length of your bed. Nice wood that is presentable. I would also place some material (that felt type) along the sides/bottoms as to not damage your paint job/bed. My idea is a "park bench" style. So you have a back for your fellow riders to rest their backs on.
I wouldnt drill holes. If you make it properly you can get it in there nice and snug up against the bed/tail gate. And if your carrying people in the back in a parade, "speeding" to the point of "falling out" shouldnt be done. I think that is the best way. It is removable, and wont damage your truck.
What I have done (for fun) is lawn chairs. We piled a bunch of ole ladies on my flat bed trailer (red hatters) and in the bed of my truck. We used lawn chairs in my truck and hay bales on the trailer. Worked great!
AND I have had lawn chairs in the back of my truck for 4th of july shows. We drive around from show to show with the coolers in the back and holden our beer's and hats down.
Now, for "driving" mode. Your looking at 2 bucket seats, bolted down, backed up against the cab of your truck with seat belts. This "I" think should only be done if your goal is to haul people around for more then just a simple parade.
Good luck, let us know what ya come up with!
Chey
LOST1953
My favorite color is CHROME
The ugliest trucks are driven by the prettiest girls

I dont suffer from insanity, I enjoy it!
O Lord, WHY did I buy another "Thing"? (again??)
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1953 Chevy 3800 1-ton Gallery More photos at MSN ----