Where can I get a tachometer signal?
 

I have a 89 GXL with a carburetor and FB distributor running through the FC trailing coil and the tach doesn't work. I am wondering where would be the best place to run the tach wire to get a signal? Thanks.

There's no way they've made an FC trailing coil work fully with a dizzy. The coil is likely dead or just firing on one side, which then goes to the distributor. So you may have a tach signal at the yellow/blue wire at the trailing. If not, you can obtain a tach signal from the - terminal of the leading coil.

Sounds like kind of a hack job to me. :(

Yeah its definitely a hack job I havent seen anyone else set one up like this on the site, but thats how I bought it and seems to be working decent. Its running great now that ive lowered the fuel pressure and messed with the idle mixture and built a 2-1 exhaust. I am slowly working working the bugs out thanks to everyone's help. Could I get a signal from where the ignition control module wires are running to the coil and I should use the negative side of the trailing coil right? Thanks.

Well I got it all figured out it is getting trailing spark and I hooked the jumper wire to the negative post on the trailing coil and now everything works and runs great. My only other question is how to adjust the trailing timing is it the vacuum diaphragm thing right below the distributor that can move in and out and which way is advanced? Thanks.

Head over to the 1st gen forum and get a copy of the 1st gen FSM. It will tell you how to adjust the trailing timing. Been a long time for me, but I believe it is the rear most vacuum diaphragm.