Joe - Here's what I found looking through a couple of resources, as well as some pics of my own ('51) 3100 drivers door latch pieces, that may help explain the differences between the earlier ('47-'51) and later ('52-'55.1) AD door latches.
From what I can see the mounting locations for the door latch and cab door opening striker areas are the same for both early and late designs. The later design allowed for some added vertical strike plate adjustment with the elongated screw holes on the strike plate itself, while the in/out striker plate adjustment with the slightly moveable screw anchor plates remains mostly the same.
You definitely must use the corresponding latch and striker plates for the desired years as early and late don't mix and match. So '52 and later latches means '52 and later strike plates. Don't forget you'll have to change to the later push button style (instead of turn down) outer operating handle which, I think, requires some mounting hole changes.
Note the picture of the bright red cab drivers door striker plate area is provided to show the recess without the strike plate installed. It's reportedly from a '52 Chevy cab and shows the slightly adjustable mounting plates the strike plate gets attached to.
To sum this up, I don't think you need to modify/change anything on the strike plate mounting area to make the later design mount or work correctly.
~ Dan 1951 Chevy 3 window 3100 Follow this story in the DITY Gallery "My Grandpa Carl's Truck and How it Became Mine" 1966 Chevelle (Wife's Hot Rod) | 2013 Chevy Silverado (Current daily driver) US Army MSG Retired (1977-1998) | Com Fac Maint Lead Tech Retired (1998-2021)
