I was struggling to figure out how to make a new bushing for the Lever Assembly that the clutch actuation rod mounts to. After a lot of searching, I came across a bushing assembly at The Parts Place. Application is a for 68-72 Skylark Upper Clutch Pushrod Bushing, part number MT3670Z. Picture below. No dimensions were given, so I just ordered one to see if I might make it work. The good news is that it will work with slight modification. I pressed out the metal shell of the previously installed bushing from the actuation arm and started measuring. The new bushing presses nicely into the arm, but the cylindrical metal spacer is too long; when installed on the clutch pushrod, the hole for the clip is covered up. The spacer is proud on both ends of the rubber bushing in the new piece, so I ground the spacer on both ends until it was flush with the rubber on both sides. Now it fits very nicely.
So, no need to reengineer a replacement bushing. Just buy one from The Parts Place and you're on your way. At $14.00 I consider it a bargain!
Chuck