shod

Hi all
I have a 77 280Z and a 78 280Z, both cars linkages binds off of idle.
When starting out I add a little fuel and not much happens, I press a little harder on the acceletator peddle and not much happens untill all at once I'm reving about 1500 R's.
I think I know where the problem is but don't know If I can get the assembly apart.

I think the problem is at the firewall mount of the linkage. The whole linkage shifts fore and aft about 3/16" of an inch while the large end of the linkage moves back and forth side to side a 32nd of an inch or a little better.

My question is this, Is linkage slider at the firewall mount a pressed unit that can not be repaired or can a guy get it a part to replace the bushings in it. I'd like to know before I pull it off the firewall so I will know if I should go scrounging for parts before I start.

Has anyone repaired this item before??
Thanks