Ticking, that's probably valetrain noise. A rod bearing makes more of a knock sound. It could also be an exhaust leak; there's a gasket at the manifold/midpipe flange that can be problematic. The exhaust leak theory also fits the location of where you hear the noise coming from and is commonly observed as a ticking sound.
Get an automotive stethescope and (engine running) probe around on the valve cover and then go underneath the car and probe it on the block, oil pan and exhaust manifold. That will pinpoint your noise.
If it's ticking from a valve, although that's not good it also isn't the end of the world. You could probably drive it forever lkke that. Rod knock is different, once that starts you ain't got much time.
2001 Laser Red GT convertible; all of the usual bolt-ons.
1967 Notch; 200 I-6, C4 auto.