Problem replacing Control arm on 1991 BMW 525i

I am attempting to replace the control arms on my old beauty (1991 BMW
525i).
The problem is that I cannot get the ball joint bolt separated from
the steering arm. It seem to be as tight as a weld.

I have driven three different size pickle forks comptetely in, and the
bolt never moved at all.

I attempted to apply heat, but am afraid of the heat damaging the
rubber of another ball joint that is attached to the crossmember.

Help! Help! help! This is my second day of agony.