Clean and degrease ends of pushrod tubes using acetone or brake cleaner.
Lube interior bore of seals. Due to expansion and contraction of PRTs during thermal cycling, tubes need to move within the seals so seals remain fully seated in engine case. There are many opinions about what lubricant to use. I like silicone grease.
Install seals, making sure ribbed “accordion” end is oriented toward the engine. Just prior to reinstalling cylinder, lightly coat exterior ribbed area with clean engine oil to prevent sticking or binding in the engine case.