[stich626]

this depends on you..
you can drop hyd lifters on the cam in there as long as you understand doing so can take out the cam lobes and if that happens you are rebuilding the engine..
if you're ok with that, by all means try it.. it's a hit of miss.. thing..
what I would do is this. take your valve cover and engine side covers off..
find a place local to you that sprays in bed liner.. stop by and ask if while spraying a truck if they'd spray the out side of the side covers and the outside of the valve cover..
you'll have to get them very clean and sand them up some..
a 6 pack of beer or a ten spot should cover the cost..(as it'll cost almost nothing for the guy to spray your small parts as he's doing a truck bed)
take them home, paint them if you don't like black/charcoal and re install..
it'll cost you the 6 pack and a few gaskets.. and be much quieter..
if the liner fix doesn't make it quiet enough for you.. you got a nice crinkle look on the covers.. and a little time spent..
good luck