Pulled the old motor out so the engine bay could be painted. Like every Escort had to tackle the rust in the heater bubble first. With spot welds removed and some gentle persuasion the damage was revealed.

It was a lot worse than I was expecting. There was a patch put in at some time with a couple of screws and plenty of silicone. You can just see it in the first photo. Cut all the rust out and started welding in the new pieces.
Because we had to cut out a lot more metal than we were expecting to, I've decided to get rid of the original fan and replace it with something more compact. So there won't be a heater bubble anymore.
Made several patches rather than trying to make it in one large piece. Turned out pretty good, a light skim of filler will have it looking perfect.
The new engine will run coil packs so this will be the perfect spot to mount them anyway.