I went to zr1.net and found an article on headlight repair by Juan Sepulveda which indicated that the bushings were available at Mid-America. I went there and found that they were approximately $5 with approximately $20 shipping.
I have two 1990 ZR1's so I needed 4 which would amount to about $40.
The big catch was that I wanted it now so I racked my brain and remembered a plastics place on 190th and Vermont in
Torrance CA and knew that they had Teflon there.
I figured that would probably work.
I went there and they told me that Derlin was Dupont's trademark for Acetal so I bought a 33 inch long rod at 7/16 diameter for a little over $3. I was so happy that I gave them $5.
I checked the depth and found that it was .4805 in. and ended up cutting them and sanding to around .465 in.
If someone has a unused one and wants to get the real value on a micrometer and send it to me, I will be happy to add it to this article.
The headlight motor now works fine. I hear that the delrin bushings are way stronger than the factory nylon and should last forever.