I finally got the courage to check the chain stretch using the cam timing mark method.

I opened the valve covers, aligned the mark on the right cam onto the mark on the tower, then read the timing mark on the crankshaft. It read at 5 to the left of the big ZERO. Here is an illustration:

pointer was between the small zero(left) and the big zero.

2|o|1|o|0|1|o|2|o

I also tried to look for the master link on the chain, but no luck. I could not figure out which one. I guess I do not really know what i was looking for. any help on this would be great.

The guides, and rail appear to be good. no cracks or missing parts. except for the color which i describe to be brown to slight dark brown.

There is this rod on top of the cam with plastic covers on the ends and about 3 more in between. I guess these are the cam oilers. The color of the plastic on the right side was brown, but the one on the left(driver's) was very dark brown.

My questions:
1. should I replace the chain? I have 150,000 miles on the car.
2. should I just repalce the upper guides and the rail?
3. what about the tensioner? should I replace it too?
4. any comments on the cam oilers? do I replace the plastics?
5. Is there another method to look for the master link? or is it important to know if the chain has been replaced before? Is the test for stretch adequate to make a decision?

The car starts fine and runs fine. to noises at startup whatsoever.

I have some pics but could not figure out how to paste them onto the body. any help on this would be great.

thx,