Originally Posted by John E
There is a slot cut in the frame like Hollenbeck's earlier Baltimore Arms and Syracuse Arms doubles. A bottom plate slides into this slot and the V- mainsprings are trapped between this plate and the hammers. The hanging sears should have springs between the sears and the top of the frame.

This link shows assy of a Syracuse double:

A disassembled Baltimore Arms double:

The drilling should be similar to the doubles but not the same.
Thank you for the I formation! When I get home I'll follow those links and see where it takes me!