One thing I learned as a mechanic was to use the metal pieces (the replacement metal) from windshield wipers (maybe a coathanger would work) and put it in a drill. Great for cleaning the tube out.

As far as the EGR valve itself, use brake cleaner, throttle body cleaner or any other strong solvent you have. Just try to keep it away from electrical devides.

I haven't personally cleaned mine yet, but chances are you'll have to use a brush and possibly a screwdriver or a small punch to open the valve to clean it well.

HTH,
Rusty

94 4Runner 3.slow-5spd, 4" coils, 1.5" BJ spacers, 2" BL, 35x12.50 Nitto's, 5.29's with a front Lockrite and a rear Detroit; 250k miles and lots of offroad time...and by offroad I mean on jackstands.