Fuel level will go into the AIM MXS on one of the analog inputs. To make that happen I needed to build cable with a pull-up resistor between +5v and the signal. (AIM have a good description of it in this PDF.) I fabridoodled it out of a 1.8K ohm resistor, some 26ga stranded wire, a Binder 719, and a couple of crimp-on Faston terminals. (Some cable sheathing, HST, and labeling for the good measure.)
Fabrication of the cable is pretty straight forward even if made a little annoying by the very tiny size of all of the components involved. I would recommend that you do this in work space with tons of light and probably a good magnifying device.
Step 1 - Preparing the resistor. Life is a lot better when you prep the resistor by wrapping/soldering leads onto either end, then sealing it in heat shrink tubing. Then it's as easy to work with as a normal wire when integrating it into wiring harnesses such as with this pull-up circuit.
Step 2 - Splicing the resistor into the signal line. In this installation, yellow will be the analog signal that has to be referenced vs +5v from the AIM dash via the pull-up resistor. To make that happen, we can need to bridge the power pin and the signal pin which is just a simple matter of splicing the one resistor lead into the signal lead. This isn't the only way to do it, it's just the way I learned to do it and it's kind of a pain on such a small stranded wire but I made it happen. Basically, you need to expose a portion of the wire you're splicing into, work a pick through the strands to make a hole. Then you insert the new wire through the gap you've created in the strands and wrap it around to form a mechanical hold. Then touch it with a lick of solder and cover it in heat-shrink.
Step The Rest - The rest of this is pretty straight forward, I won't go into detail about it. Just pre-tin the connector and wire leads, that will make things go much smoother. It's also a good idea to think about labeling and cable sheathing while you're at it.