Using the throttle lock to hold throttle wide open I sprayed Startron Carbon eliminator into each intake tract and top of all 4 intake valves - all the intake valves allowed cleaner to pool so engine shuts down in that position -
Using large lockable industrial forceps with rounded tips ( so no scratching intake tract or valve heads ) I locked pieces of clean new shop rag into the jaws and went down each intake tract cleaning off oil and carbon around the valve bowls -
Over a couple days I let decarbonizer chew at soft & hard carbon deposits on the valves, as usual left fwd valve is worst, fully cleaning out all areas - removing loose debris with shop rag strips on forceps keeps abrasive carbon out of the piston and ring area -
After cleanup I modified a see thru vitamin bottle with holes in the lid, a length of heat bent nylon tubing and tee shirt material for a lid vent filter and using oil resistant RTV, sealed the hose into the oil separator vent outlet and bottle base in place in the airbox, using a final metal lock type nylon Tyrap to attach the oil storage bottle to the H-D oil separator.
Works great, and very low cost - not seeing any oil in the airbox or inlet tract so far so I'm sure they will remain clean, dry and oil contamination free.
Tip - be sure to remove H-D oil separator cap by depressing two push locks with small straight tip screwdrivers, clean sep pads of oil, dry, re-install and oil resistant RTV the cap back on to keep oil from spitting out of the cover gap into the airbox.