Rear shock install_problems

Hi there.

I have a 67 Dart and new Hotchkis shocks. I am totally struggling to slide on the shock/bushing onto the upper shock mount/ peg. It is all lubed up like a suckling pig, tried warm water to soften the rubber but only goes on just over halfway. I have tried gently tapping on with a mallet, different angles, wiggling AND jiggling. I have wrestled enough. The measurements are tight but not impossible.

What am I doing wrong?

Cheers, Andy