Your Wild Beat is looking great David!!
Others may have some better opinions in the MK Bellcrank...I've only installed two which were in ARF airplanes and I made an access hole/hatch in the bottom of the fuse...I think next go round I'm going to try not to do the access hatch and try something different...Here is what I was thinking (if I can explain it so it makes sense??)
The MK bellcrank comes apart when you remove the socket head cap screw which is on one side...You can break it down so that you have the center control arm piece all by itself...I'm using central hobbies carbon fiber rods so I was going to attach the center control arm to the end of the CF pushrod and fish it back into the fuse...I imagine it will take a little patience but once I got the end lined up with the holes I would "assemble" the MK Bellcank in the aft fuse....
I'm pretty sure it will work because I actually had to remove and re-install one of my existing planes and did not use the access hatch to do it...It was really pretty easy...
Not sure if that makes any sense?? I wish I had some photos..Maybe when you disassemble yours it will be more clear...
Have Fun...
Chuck