Technical Quick change adapter plates

Was looking to see if anybody had a quick change 12-10 bolt adapter side plate, Ik their rare but got a buddy who wants to try to make some new ones, and need the correct measurements and sizes saw some for sale online but sold before I could buy.

 

Do you have a good picture?

 

The Hambs quickchange guru, Gearheadsqce ( hamb name), used to make them but I believe he p***ed ( last seen here July 2025). I guess any of his unpublished do***ented knowledge is lost. Sad.

Chris