The ECM power wire is pink with a black stripe. It goes from the 10A ECM fuse under the dash ( bundled with a bunch of other ECM wires ) to a big black connecter ( it's actually 2 big connecters ) which would be in the area right under the glovebox. You can just have the wire from your choke go into the car ( see below for how I did it ) and plug right into the 'F' pin on this big black connector.
This double black connector connected to a big whitish colored connecter which went to the ECM and also had wires that went through the grommet ( located right there in the in the wirewall by the ECM ). Since you don't use the computer, this white connector, the ECM, and all the wires that go through the rubber grommet out into the engine compartment can all be removed. On my car, I removed all of that and have my electric choke wire ( and converter lockup wire too ) going through this grommet and connected to the proper pins ( F for the choke and the P for lockup ) on the big double black connector. You don't have to do it that way yourself, but that's just the way I did it because it was clean and looked factory with no wire hacking or holes drilled into the firewall.
Since you already have the test light, I'm sure you can find a wire that's under the hood for easier tapping ( try the windsheild wipers ), but I personnaly I don't like splicing wires ( or drilling holes ), and I always try to avoid doing so if I can.