I saw someone build a roll cage for their truck recently...I will see if I can find it. I know they were going to race the truck, so not sure if it was removable like you want or stationary.
On a side note,I agree with your above post. It is your truck; enjoy it and build it to make you happy. I have said when I take my truck to shows, I know some people won't like it..and I am fine with that...I am thinking of having a suggestion bucket...that cost the person a minimum of $5 for the suggestion!
I have built mine not as a show truck, but a truck to enjoy, drive, and use as a truck. My wife and I love our truck and that is the only ones that matter or gets a vote.