Interestingly this shield is rather similar to the one used on 70 B-bodies. In section 12-04-4 of the parts book it lists 2925315 for both B-bodies and E bodies with 340. There was a technical service bulletin for 71 model year that announced the 340 ebodies were going to have a fast ratio box after a certain date. On this bulletin it makes mention of this splash shield and refers to it as part number 3583003 and lists the rubber seal as 3583004.

Attached is a picture of the backside of my T/A shield and below I will attach what I have been told is a 70 B-body shield. To me it looks like you can modify the B-body one to make an E-body.