[TR] TR2/3 ball joint installation problems

[Angelo Graham]

Hello List:
Trying (again) to install a new set of ball joints to the upper 
control arms on my TR2 project. The joints are supposed to "cut" into 
the pressed metal with the splines. No luck whatsoever and about 1/4" 
of the splines are visible and the joint does not fit snuggly against 
the control arm. Doesn't seem that the old spline groves help with 
this either. Using TRF's  ball joints.
Have followed the manual instructions and description of the arm 
overlap. Don't want to strip the joint threads by using excessive 
impact wrench force. Would a press work better??
A couple of friends with good mechanical background have tried to 
help, but no luck.
Why should something so simple be so tough??
Any hints or past experiences?
Thanks for your help with this.

Angelo Graham