Thanks all! Oddly enough I didn't get any email notifications for these responses. After digging deep into my memories, I remembered that I once used a timing cover bolt. I used the two longest ones as suggested and just pulled off the sprocket using a puller.
I'm not sure what the deal is with my car. Both the harmonic balancer and the sprocket had the slightest amount of play. From what I recall, they shouldn't have any play. I could pull them towards me ever so slightly but I needed to use my puller to remove them from the crank completely. It appears that there is a ridge on the key; if it is in fact worn, it doesn't appear to be worn uniformly. I think the wear is more towards the oil pump. There's a lot of rust dust on the crank snout. I've wiped some of it off and the crank seems fine (whew!).
Another potential problem is that one of my crank sensor screws has worked itself loose and is halfway out of the sensor. I was able to jiggle the sensor a little bit.
I think I'm dealing with two issues here; a worn key that I caught in time (I hope) and a bad signal from a loose CPS. Very odd...
To add to this, I knew I had a timing problem when the car starting running rough in the summer. I pulled the upper timing covers and found that the adjustable sprockets had walked. After resetting them to 0 retard/advance (and installing lock washers) the problem was better but never went away. I wonder if the belt stretched or jumped a tooth when that happened. If the crank bolt was loose, it may have exacerbated any key wearing issues. I may never know. I didn't have time or a place to work on it so I ended up parking the car until now. Thankfully I have another daily driver, time AND a place to work on the car again.
Thanks for all of the help!
I think I have a line on a used key, sprocket and balancer. I have a new timing belt and crank sensor to install. I hope this fixes her; I actually miss driving the SHO (sometimes).
Ian
