Is it OK/how to clean a Coill - on - Plug Ignition Coil?

Changing spark plugs. Ignition coils' dilectric grease / boot protector lube that I applied to the inside of the boot, last time I changed plugs, was discolored, smelled HORRIBLE, & was yellow-- a little dry... "Pasty". Appearing to possibly no longer possess luricating qualities.
1) Is this normal, or a sign of a problem?;
2) Just as a matter of semi-routine maintenance, even if the "pasty" problem wasn't an issue, is it OK to clean " Coil - on -Plug " ("C.O.P.") spring - coils / boots? If so, how?: Brake cleaner on spring-coil & soapy water & a small brush in/on rubber boot That's my guess(?)
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The discoloration is normal. It should cause no problem. As far as cleaning the boots, anything that will not deteriorate the coil will work. Cleaning the spring can be completed with anything that will take the old grease and dirt off the spring.

Great-- I'll try all of that! Thanks, as usual, WTO!
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