Need help with an adapter plate identification

Hi group. I am in need of some information.
I am looking for a very specific application adapter plate. Some 20 years ago, a number of Chevy P30 delivery vans were factory repowered from gassers
to 4B Cummins engines. The adapter plate was designed to bolt the Cummins B block to the TH400.
Now question being, Does anyone know if the adapter was a GM part or a Cummins part? Or has anyone ever even heard of this piece? I am searching for one.
thanks.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Found today, it is a Cummins part (#3916101)
I'm repowering my '86 crew cab 4x4, with a 5.9cummins out of a '95 Dodge and useing the th400/205 with this adapter.

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Motorsforum.com is a website by car enthusiasts for car enthusiasts. It is not affiliated with any of the car or spare part manufacturers or car dealers discussed here. All logos and trade names are the property of their respective owners.