Servo horn for Savox servo B44.2

[AfroP]

Just at the electrics/servo install part of my B44.2 and so far everything has run smoothly

but when i get to the bit for installing the servo,I cannot get a kit supplied servo horn to fit.
Normally for a savox servo i use a 25t or Futaba horn, but the kit supplied futaba horn is either too small or too tight of a fit to actually go on my servo.

has anybody else had this issue?
any advice would be appreciated

thanks