Finally joined after a while browsing.

In the not to distant future I aim to purchase a tag axle denning/austral coach to convert into a motorhome. Having previously fitted out a Toyota coaster and travelled for a while I can't wait to do it in something a lot bigger.
One thing that slightly concerns me is the internal roof height. The coaster was right on the limit with me having to twist my head if I had shoes on, it was a bit annoying bit still livable. I was in a denning denair the other day and roof height seemed fine in the centre, but towards the outer edges of the aisle it was a bit low for me.
One thing I have seen a fair bit of is people raising the roof of their coaches 2-300mm to gain internal height. While this would be nice I just don't have the room or $$$ to do that. As I will be doing most of the conversion myself it just isn't practical to go to that extent of frame work just for a little bit of comfort.
What I have thought though is there any way to lower the floor? If I could lower the floor so the whole width was the same as the aisle it would be fine. Obviously that would cut into storage in the bins under neath but I doubt I would be able to fill them while travelling anyway. Also it might not be possible around the rear wheels due clearance but if I could do it from the front to the rear wheels it would probably be enough.
Admittedly I haven't had a good look under neath but it does look possible from the pics I have seen. The only issue I can think of is if the main frame rails run down each side of the aisle.
Does anyone think this is possible? Could I lower the floor in this way?
Any help would be greatly appreciated. Even if you have some pics of the thru-bins showing the underneath of the aisle as most show the floor of the bins from what I have seen.
Thanks in advance,
Cary.