That above is not the dovetail, just the latch The Dovetail is as in @catmans's pic above, that one is badly out of line and will not do the job of preventing door moving up and down when shut.
The brass tail is a cast shaped item that locates into the bent steel tapered U that is located on the cast bracket behind. It then has shims between it and tub to get correct adjustment.
Try and find the parts as recon not an easy thing to make.