Okay went out to the garage after shoveling ,We had no snow 3 days ago looked like early spring then this.Anyway I took a few pictures of my 54 door Canadian model if you notice no clutch head screws .I think you will need the two plates behind the striker pate as you will notice a raised metal line and the plates have groves to hold the plate in place when screwed tight. One horizontal and one vertical on the opposite side .the plates don’t seem to make the plate stick out any farther .the latch I took 3 pictures open first click and second click or closed.I took my plate off to show there are caged nuts behind and there is a slot in the door pillar for some adjustment .hope it helps.On your 53 is the door correct with vent windows . The earlier doors had different latch but yours look correct .
