I would check the spark plugs as well. Also if the spark plug boot has oil on it, your valve cover gasket tube seal is leaking. When I did my t-belt, I ended up doing that as well, as I was close to it.
Consider doing the valve cover gasket+ the sparkplug tube gaskets.
Also I'm assuming you're including the tensioner in with the pulleys?
I would also check the big crank pulley to make sure it isn't falling apart.
I would also check over the hoses and replace if they're starting to look old and also check the black plastic endtanks on the radiator, they do tend to split with age.
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