The console I have on my Ocean 6.5 made by Windsor Brothers is large enough to get behind, and there's room inside for a portaloo!
I only have a short screen fitted, but others have gone higher.
Hightower had them build him a special one with a cut out for his long legs.
His build thread shouldn't be too hard to find.
Pete7 also fitted one to his Pacific which was covered by one of the longest ever Rib.net threads
Here are some pictures of it.
Nasher