I got my NG3 back in the late '90s so I don't know how he sells them now, but I started out with a 5-speed (365) and that hoop didn't look like it was going to work at all so when I mentioned it to Richard, he sent me a new hoop that either was or was similar to the hoop for a 336 without the mounting ears. I don't remember if he took one off an old frame, was a bit he normally supplied, or he made it for me. Richard supplied the tranny mounts and I had to have the hoop drilled so that tubes could be welded for bolts to go through the hoop to the mounts. It's pretty simple but I'm having a hard time describing it. I can post a picture if you want. My body was off but I suppose it could be done the the body on, but it would probably be a bit harder.
I like his twin link rear suspension, too. As I remember, it was a bolt on job, but I might have gotten uprights from him at some point (that was SO long ago!). Everything he makes is great! He'll send you everything you need! He's a super guy to work with. You should check with him about what's required to fit all that stuff now. It may have changed and my memory is sometimes a little fuzzy!