Recommendation opinion
I know everyone has an opinion (they're like ***holes) but I would really recommend taking your engine out to do this.
If you need timing and balance chains, you could also probably benefit from new bearings and rings as well as a thorough cleaning. Technically all of these things are doable when the engine is in the car, but if you add the pain of trying to do them all that way, it probably adds up to easier to pull it.
And the process of tapping the dowel pins for removal of the timing cover is likely to be really painful with the engine in the car, not to mention getting it to seal properly with the joint between it, the head and the block.
Pulling the engine is not that tough. With an auto, it's probably a day's job. Some here have done a pull, chains, and reinstall in a long day.
Anyway, one opinion.