Thought I would share this. A good while ago I managed to find a Pentax TS-110. The idea was to convert it for use with my K10D or K20.
Cameras moved on, but not so my project! Now with a K3, I thought it high time I got going with this.

Basically, I removed the old wiring and plug and replaced it with an Amazon purchased lead with a 2.5mm moulded jack plug already attached.
With a low power soldering iron, with a small bit, I desoldered the old wiring. Careful to note the colours and the locations on the circuit board.
iPhone camera and took a few pics.

Once the cable was stripped back on the new lead, I carefully glued the outer cover into the old cable clamp shroud. (That was the only piece of the old cable that I re-used. Oh and of course I retained the cable velcro cable tie!

Attached are a couple of photos and a drawing, should anyone else think of doing the same modification.

Thanks to a Forum member, I was able to obtain a copy of the user manual too

[strixaluco01]

Hello, I was very keen to buy a TS-110 for my Pentax 645 NII but I was shocked to see how expensive are the very few left. Hence I decided to build one myself. I bought JJC TM-C intervalometer for £18 and I sacrificed a CS-105 cable. At the other end of the CS-105 I soldered a 2.5 mm female stereo jack to which I connected the JJC TM-C et voila' all works well, including the autofocus.
I made the most of the "sacrificed" CA-105 remote cable left by soldering to the other end that I had cut (which had the jack for the 645 NII socket) a male 2.5mm stereo jack, so I can use it like before with my Pentax 645 NII (if connected to the DIY cable) or directly to my K-3.