Size .156

LTG : )

Don't use the idc type get the crimps and tool instead. Pinrepair.com and pinwiki have details on how to crimp.

Wire bot has the parts

Strongly second this.

While if you get perfect wire insertion into an IDC connector you'll have just as good a current handling capability as you would with crimp-and-stuff plug housings and trifurcon terminals, trifurcon terminals have superior vibration resistance.

Pinballs are almost the definition of a high-vibration environment.

Here are the Trifurcon terminals:

https://wirebot.xyz/products/trifurcon-0-156-crimp-contact

Here is the 11 pin crimp and stuff housing:

https://wirebot.xyz/products/0-156-connector-housing-w-locking-ramp?variant=42171288748278

A polarizing key makes it easier for the next technician to know where this plug goes, and prevents incorrect plug placement that might in the future damage your machine:

https://wirebot.xyz/products/0-156-polarizing-key?pr_prod_strat=jac&pr_rec_id=f59cb2c0b&pr_rec_pid=7470029504758&pr_ref_pid=7437240795382&pr_seq=uniform

You'll need a crimper. Here is a thread about inexpensive budget crimpers. I would use these:

https://pinside.com/pinball/forum/topic/favorite-budget-minded-molex-crimper-#post-8041111

Don't do half the job. The pins on the board are also compromised due to heat. These pins break off to the correct length:

https://wirebot.xyz/products/0-156-24-pin-header-w-locking-tab

When soldering the new pins in, the plugs at 121 and 120 are identically connected. It's easy to not make connection to traces on top of the board. Use a meter and check that each pin on J120 and J121 are connected to each other.

https://pinwiki.com/wiki/index.php/Williams_WPC#Game_resets

Multiple possible causes. Work through this list. Or buy a Kahr board.

Kahr board masks it for a while eventually you'll be working the list might as well do it up front

You know the pins and plugs I recommended before?

There are a LOT of reasons why you 'hit both flippers and bong' (WPC resets).

You definitely need to read the whole section on the wiki.

But lately, I've gotten to one particular recommendation, and that's what has been consistently fixing it.

This is replacing connectors (even though they aren't browned, and while they may or may not be heat tarnished, they definitely have wear...).

So, it's the 5v I'm worried about, and that comes in on the power driver driver board on J101.

This is on the upper right side of the board, the plug closest to the middle of the right side.

Like your connectors for the General Illumination these are .156 terminals, and you'll need to replace pins and plugs. Get the 7 pin plug and socket for this.

Right above it is J102, and while this is not your problem, look at this connector. If it's got toasted pins or looks worn, consider replacing J102 while you are here (this is where the other voltages come in). Get the 9 pin plug and socket if this needs replacement.

J101 is where +5v comes in, and it goes out on J114 (on the opposite side of the board, left side, under the fat ribbon cable).

J114 is a 7 pin plug.

So I replace those two connectors, pins and plugs with trifurcon crimp and stuff (don't do half the job).

Finally, on the CPU board, the +5v comes in on J210, again this is .156 terminals. 7 pin. Replace pins and plugs, with crimp-and-stuff housings, and trifurcon terminals.

For a LOT of years, other things in the wiki recommendations would get the 'hit both flippers and bong' problem' fixed.

But for the last year or two, it's pretty consistent that I might do other things, but THIS (replacing three connectors) is what get's the game reliable again.

Don't neglect the Wiki article!

But don't be surprised if replacing these three connectors is what resolves the problem.