Just fixed a Hot Tip with almost the exact same problem. Because of the location of the batteries it wasn't actually that bad to fix. That left chip and the two roms can be replaced with a single combo rom in the far-right rom socket (not populated on your board). Replace the interconnect and ROM+CMOS ram socket for good measure and I bet it'll boot right up. There aren't many good replacement boards for early williams...

If it becomes too difficult to fix though, Rottendog makes a replacement CPU/Driver board combo.

Alternatively, you can always look at classifieds here, or throw up a wanted ad. If I recall correctly, the System 3-6 boardset are all backwards compatible (i.e. If you can find a working System 6 board, it'll work fine in a System 3 game, provided you have the right Flipper ROMs installed), and jumper the boards properly.

You could always find a nicer original board to repair, or find a refurbished one that someone has already repaired.

Also try a WTB ad in the marketplace if you can't find something listed for sale.

Rottendog has a combo board for the MPU & driver board, but it's a little on the pricey side.

Vid's system 3-7 guide should give you a good overview: https://pinside.com/pinball/forum/topic/vids-guide-to-bulletproofing-williams-system-6

I just pulled those three chips (IC 21,22,25) off completely, and replaced the sockets for 17, 19, + 20. Get a new rom for IC 14. If the corrosion reached the big connector along the bottom, replace it. Sand the corroded area till you've got nice shiny copper anywhere you had corrosion, clean it off with vinegar, water, and alcohol. Unlike other manufacturers (gottlieb, bally), the battery isn't near the reset area on williams boards, so the battery can do a lot less damage and they're more salvagable

You need to neutralize the alkaline from the battery leakage, or it will continue to eat away at the copper.

Vinegar isn't acidic enough to neutralize. Take a look here:

https://pinside.com/pinball/forum/topic/stripping-battery-corrosion-with-a-strong-acid

Then sand down to the copper where the batter damage was, add your new components, and seal exposed copper with clear nail polish.

IC14 is the unpopulated rom socket on the right of the other ones. You can see the empty pads in your picture.

Interesting! I've always been told to use apple cider or white vinegar, *after* sanding. Then again by the time I'm done sanding I don't think there's much left... A pain though

With zep, it attacks the alkaline chemically, so I actually end up doing a bit less sanding since most of the alkaline is removed before getting to that point.

Replace any parts that are hit with battery leakage with new parts. That leakage can spread like a virus and continue to corrode and damage the board if any of it is left behind.