Timing chain confusion.

[clay68c10]

I like step 4 1/2, good idea to make sure you have the right balancer.

That book will be very helpful.

Your description of the chain slack sounds like you will need to replace it.

I'd pull the pan, the gaskets don't always like to seal back up after they've been disturbed. But, you could always give it a try without fully removing it. Maybe it'll reseal. If it doesn't you can pull it later and it won't disturb the front cover.