Sidetracking a bit..but never mind
Tractors are fine, prop in slot gives more airflow over the control surfaces, so fastest response. Rear mounted still works, but airflow over controls now totaly depending on forward speed.
Each has its plus and minus..
I think the trike gear works ok because its a long version. And it wont pull away easily.
I use this alternative two legged method on the nutball see pics below ( 2mins in sketchup )
The blue line is some CF rod to hold the thing on.. the cross bars are just long enough to make the UC a tight fit on the fuz..the v section pushes down on each of the sides of the fuz
The sketchup does do the job well. It makes size changes a doddle...etc and the nutball is a great aircraft... although if you build with depron I will recommend a top 50% KF step about 10mm total depth tapered down on the tip section, it stiffens up the wing a treat
For the wing tips
Ive found a heat gut that works well..pic 3 of this post would be ideal for the nutball..no cut and stick needed and the bend is just as strong as the rest