And check the free rotation of the oil pump. I think the oil pump chain is stretched, too. When you intstall the new lower oil pump chain guide, there are two mounting bolt holes. Oval out the more central one with a dremel or drill or rattail file, so you can pivot the guide a little to adjust the clearance to about 1mm, and that's all the slack there should be in that chain.

Not responsible for advice not taken...