Still not further on, as I still need to hook up with my mate to do some soldering and try to find a work around for the on/off switch in the GPS tablet. I've discovered that if I bridge the points where the press switch used to be, the tablet will power up. However, if the points remain bridge, it will turn itself off again after a few seconds - and it can only be rebooted by removing the bridge, and rebridging it. So, I need to find a work around that will allows these two points to remain physically bridged, but only allow a power flow through them fir the first few seconds, then after that either divert the power flow somewhere else or interrupt it. Something like a pulse power circuit, or in layman terms (and I'm a fucking layman when it comes to this ) a "gate"

On a brighter note, I got hold of the original plug that fits this nav housing, only to find after receiving it, the pin connections aren't quite as they should be. Seems it's from an earlier model, and although the plastic plug is the same, it's missing some connections for the pins I need to use. So I reverted to the original plan of cutting up a computer molex connecter - one end of which will have female spade crimps on the wires, which will attach to the pins on the nav housing, and the other end of which will be hard wired into the stereo wiring. Turns out, that's easier said than done, as the smallest crimps are just that teensy bit too big; they can be made to fit, but they touch. I could insulate them with heat shrink, but I'm still not 100% convinced.

So I looked out a brand new ISO harness I've had in a drawer for years and years and never used (think it's ISO to mk4 Escort plugs) and hacked that about until I got two of the female pin receivers out, with their wires. Not a direct fit into the Lexus nav plug, but a bit of bending and squashing with some pliers and I got them in, and with a bit of careful angling, the plug fits in the nav, and all connections are made - tested it hooked up to a car battery and (same as the video above) and all functions work. So that's pretty cool, as all I'll need to do now is put a half metre or so of wiring on each of the 5 wires, insulate and wrap them, then they can be spliced directly into the stereo wiring for power, ground, and illumination

Ordered me some heat shrink and a "my first soldering set" off eBay, so when that arrives I'll have a go at extending the wires, fit the two-pin plug to the GPS power wires (so that that can be plugged and unplugged at the dash-top end too) and hopefully won't be long after that, that we can start on trying to hack the power button on the GPS tablet