1995 with crank keyway damage

2013 Mazda CX-5, 2.0 Manual Transmission, 1989 Mazda MX-6
I have been looking for a good old un-modded Miata in Portland area ( not easy ). So far I found one at about $3,000 over book price.
So now I am considering this 1995 R package Miata ( pretty much the model I want, and a good deal at $2700 ). Someone did not torque down the center crank bolt after timing belt change. The car has 100,000 miles. Seems like unnecessary damage, since I don't believe the center bolt needs to be removed for a timing belt change, only if you need to replace the crank seal.

I am not an engineer, but my thinking is, the only purpose the crank key makes is for lining things up, then a properly torqued center bolt is what keeps things in place. If it was there to keep things in place, then it will always become damaged no matter how much the bolt is torqued.

If somebody knows that I am wrong please let me know.

Also I owned a 1990 626 for over 20 years. I made the same mistake on my last crank seal replacement. I did a loctite 660 repair. And it worked. Not sure if I really needed the loctite or not. But I drove it for another 50,000 miles before I gave that car to a friend.
The car had over 300,000 miles at the time of repair, so with a new seal, I did not worry about having to remove the crank gear for a long time.

I would not really want to use loctite on the Miata given the low miles, and with proper maintenance it will last for many hundred of thousands of miles like the 626. Seems like once I use the loctite the Key will be stuck there forever, and won't be able to replace the crank seal if it starts to leak.

Edit: Someone already got to the car before I could. Guess I will wait for the next one
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