Yes, Thanx Lightfoot for posting the two images together.

Here are some measurements that may or may not be the same as Eric's. 1899B ; Distance between holes Center to Center along the top of the receiver = 1 11/16 ".

Both holes are 1/4 " down from the top edge of the opening in the receiver.

Distance from center of back hole to after end of receiver opening (after most curved part) = 21/32".

Both holes have only 2 1/2 or 3 threads, (8-32 threads) and don't go right through to the inside of the action. (The OD of an 8-32 screw is 5/32").

Maybe The T-7 mount was being sliced lengthwise and holes drilled up higher closer to where the mounts are, and thereby eliminating all the extra sheet metal laying along the side of the action.

Last edited by Malcolm; 07/08/18.