[nxtruck]

I was in this situation a few years ago. I had a couple of the cheap Jaz racing seats in my '66. My kids were getting older and wanting to ride along with me to cruises and such. I couldn't take them both at the same time, so I started looking into trying to fit some sort of small seat between the existing seats. I also have a rollcage to work around, so moving the seats much was out of the question. I ended up using a bench seat out of a '90 Chevy truck, as it was narrower than the factory bench and would still allow me to carry two passengers, not to mention fitting in between the cage. It's pretty comfortable, too.
Just my .02 worth.