tach question

[dewfamily]

I have just finished installing a HEI in my 88 Wrangler. I cranked the 258 up and the tach was working. I cleaned up under the hood by removing burnt wires and plug ends that were covered up by po. The tach wire ran to the igniton box and was spliced into the harness going to the computer. Now the tach won't work. My question is does the signal go to the computer and then to the tach? Or do I need to tear all the wires back out of the wire loom?