i'm all wired up and sva ready, and i'm a total tw4t and i've forgotten to run a wire for the temp guage, and i used the sensor for mega squirt, so heres the question.

how about i use the sensor for the temp guage and put a varable resistor in for the maga squirt bit like a choke?

i dont really want to start pulling wires out his close to sva

That should work, the temperature sensor only operates up to a preset point after which the temerature has no effect.It is only really for warm up enrichment so you could just set it to warm up and then turn it back to the warm setting before emission testing.
But surely it wouldnt be to dificult to add just one wire for the sensor even if it is just taped to the loom neatly.
Paul.

If you're in a hurry i'd go with the resistor. I'd consider having two fixed resistors (say one 100ohm and one about 2k ohm, or whatever corresponds to room temp and running temp on the sensor your MS is setup to use) and a switch to switch between the two. Should be cheaper than getting a decent pot that will be easily adjustable over the full range, and a switch is easier than twiddling a pot.

Sharing the sensor with the gauge isn't as simple as running another wire from the sensor. Both the gauge and MS have an internal bias resistance to form a voltage divider with the sensor, attaching them all together will upset the voltage divider each device is trying to form and throw their readings off. If they both operate off similar reference voltages then you can get around it by removing the bias resistor in the MS and configuring it according to the other, but it may be easier to just find somewhere to add another sensor, or use a dual output sensor.

I can tell you from experience that MS will not share it's temp sensor with a gauge. The MS thinks that the temp is 40 below and runs the enrichment. I got caught out on this just hours before hitting the track.

Your engine head must have a threaded bung on it where you can add a sensor for the gauge? Usually there's sensors all over those beasts.