Below you see a fellow bike-hacker (actually he's building a big electric carrier bike) modeling on the HR to show the lack of knee/handlebar clearance.
Wouter shows there's no room for the legs
No other option than to cut the goose neck!
This is my HR in its current state. I made the gooseneck extra long (since it easier to make it shorter than longer afterward).
There is plenty enough room now for the knees. The steering is a bit less nice than before though. The longer goose neck adds extra tiller of course and it also flexes a little..
Besides these details it is an absolute blast to ride! It is fast, comfortable and the view is great. And I'm very glad the HR is high enough for people to see you, even cars when you're next to them. I also found out that you DO can see quite a lot behind you by turning the neck and looking over the shoulder. Still thinking about mirrors though. Today I also took some detours over grass, gravel, or curbs for the fun and to overtake people. The bike handles it fine!
I asked the guy from the recumbent shop/factory in this town if he could hook me up with some extra long brake and shifter cables and he said he could. Then I will FINALLY install it, do the final adjustments and tidying and then.. paint!