200K on timing chain assembly, time to replace?

This thread is somewhat related to my last thread about the codes. I'm getting 28,29,42 and the speedometer stops working randomly. I just wonder if the old timing chain has slipped or loosened to the point that it's causing my problem? Car is running VERY rich too. I can't afford to through uneeded parts at 100 bucks a piece at this old car.

Any Ideas?

Turn the crank back and forth using the retaining bolt you will feel the amount of slop in the chain doing this.

You have three codes, none of which are directly related to a timing chain problem.

Code 28
2 flashes, pause, 8 flashes
3rd gear switch was closed or grounded for 10 seconds when vehicle was in 4th gear, or 3rd or 4th gear switch was open when engine was first started.

Code 29
2 flashes, pause, 9 flashes
4th gear switch was closed or grounded for 10 seconds when vehicle was in 4th gear, or 4th gear switch was open when engine was first started.

Code 42
4 flashes, pause, 2 flashes
The Electronic Spark Timing (EST) signal did not change when the ECM applied bypass voltage to the ignition module. Check for faulty connections, or a faulty ignition module.