Battery Leakage Again

A recent purchase:

It's a Casio FX502P in pretty much perfect cosmetic condition. Unfortunately the display isn't. It's not displaying anything very well at all. It's attempt at displaying Pi shows how bad the LCD is:

Once I opened it up, the problem was immediately obvious. It was battery leakage again. It's not very obvious in this photo but the batteries have leaked in the area of the battery contacts (which are remarkably clean) and the LCD. 

The LCD is fortunately connected with zebra strips on this calculator, not heat seal:

This meant that I could dismantle the display and clean it. I also cleaned the tracks that had had leakage on them. the solder resist was loose so I removed it on any affected tracks. You can see that tracks I've cleaned are missing their resist and appear gold in this photo:

Once re-assembled, the LCD is working perfectly. It's got good contrast and the filter is completely free of scratches. It's the best example of a FX502P I've got.