First,
dcb1!!
Second, I don't know the details about Richard's bodyshell. I would assume that they would be a pretty direct replacement of an original but would probably have some improvements. A call to Richard should get you the answer. I advise calling as he's not much for doing email.
Third, whether you'd fit or not depends a lot on where you are tall. I know a guy who is at least 6'3" and he says he's comfortable in his stock Europa. I think he's tall in the legs and he bends them a little. When I was just about 6'2" (I'm 6'1 1/2" now, but I compressed!) and I was comfortable in my car and I drive with my legs straight out. I admit that my hair brushed up against the headliner which was mildly annoying when I thought about it.
Fourth, I'm apparently tall above the waist. When I rebuilt my car, I put a bubble (like a Gurney bubble) in the roof. It gives me a couple of inches of extra headroom. The headliner conforms to it perfectly and it's a BIG attention getter! Once you have a pattern, it's pretty simple to do. There is a downside and that is that when looking out of the driver's window near the top of the window your vision is restricted a bit. This is annoying when turning right at a stop sign (for you, it would be when you're turning left). I don't consider it dangerous as it is not an issue when I'm driving.
Fifth, some people delete the seat adjustment mechanism and bolt their seat directly to the floor. That gives an inch or two more head room.
You might discuss mods you could make to the body with Richard. I considered lowering the back of the floor an inch or so but since my seat was going to be against the firewall, I figured I'd need to make changes to the firewall and the struts for the seatbelts behind the firewall so I abandoned the idea. It's possible that there other body or seat mods that would help.
Let us know what you do! Good luck!