Best six dollars you’ve ever spent - between fresh coupler bushings and this firewall bushing the overall shift action and control has been transformed.
There are probably other ways to do this but here’s how I went after it;
1) removed the shift coupler cone screw
2) separated the front shift rod from the coupler
3) remove the shifter assembly from it’s mount inside the car
4) put the replacement firewall bushing in near boiling water for five minutes
5) pressed the firewall bushing into the open part of a 1 inch socket to help compress the part that pushes into the firewall
6) removed it from the 1 inch socket and pressed it into the firewall using my hands
7) pushed the front shifter rod back through the firewall and reconnected it at the coupler with the cone screw
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