All advice is appreciated. I did setup a shop stool inside at roughly the height above floor level that I'm thinking my seats will sit. That was easy with no floor whatsoever in the cab I set the kick panel back in place and sat there for awhile. I taped paper over the windows at different levels to check visibility and also used a block on the current roof to check headroom. If my seats sit the way I think they will, I should have a few inches of headroom when I'm sitting straight up and a fair bit more when leaning back. I'm 6'2" so that should fit most people OK I think that the dash is quite a bit smaller than in my Willys because I feel like I have a lot more space in this one than I do in it. Of coarse, it's channeled 4.5 inches...