Here are some article on z scale coupler conversions:
The above links are brought to you by Peter of P&amp;C Railroad fame. He recently sent out an email about his current situation. I quote from part of the email.
"The P &amp; C Railroad web site will soon be discontinued. However, we have
gotten, and continue to get, so much wonderful feedback, that I have
decided to move all of the P &amp; C Railroad web site content to the new
company web site. The company's web site address is:
I am personally very sad to see this fantastic resource go away. I wish Peter all the best with his new endeavor.