Bad Raven, Keith,
Thanks very much for your help again. Was just against a brick wall with Brain failure. Couldn't see the woods for the trees!!
Hadn't fixed any servo's or started, just setting out my stall in readiness to start, when the servo placement confusion set in as I loosely placed servo's.
Really was obvious when I downloaded the 450 Pro manual and spotted servo screw holes in the cross bars within the body.
Yes the rear servo needs to go inside the body. Using MG90's with a DS520 for the tail and am going to try the 401b see what happens. I have genuine GY401 or Align gyro's on my others. Thought I would give the HK401b a try for the price. Many saying its good, others saying its tosh.
Thanks for your advice regarding the potential for tail gear stripping. All my other heli's are belt driven, will see how I get on, may change to belt, I did think about crashes and the bending of the drive shaft as well. (And I have been known to crash now and then!!!!)
Never had an issue with a belt driven Heli, fancied a change and try a shaft driven tail.
As for the HK450 Pro, pretty impressed with the quality and price. I built an Align Trex 250 (super Combo), and I have to say, cant tell the difference in quality of the parts between that and the HK 450. Very impressed for the money. It appears as if the major issues/complaints are the quality of the screws etc. But for £45.00 you do get a lot. Up to now, well done to GShark for getting this in.
Thanks to all again for your help.