chemie,
I wish I had an answer for you. Maybe with dry fitting there is enough "play" to get the 8oz tank out. I dunno, but I tried mine every which way I could, and it would not come out.
h@h,
That is a great idea! I did use one of those flex tanks once on my Mustang. It was sitting against a former, and after about 20 flights, it had a groove worn almost all the way through the tank. That problem should be eliminated by gluing foam to the tank. Also, lowering the floor is what I would have done, if I ever build another SSE. But I like the "no floor" idea even better, as long as the tank is not sitting on the lower cross brace, or protected by foam. I would also mount the engine sideways and build a cowl. I think the extra work is worth it, looks wise.
chemie,
You might want to check this out. Sounds like it worked pertty good for h@h. If you use a flex tank, just be carefull and make sure that it is not rubbing against any "edge" surface, like dummy me did.