With BP you're gonna get dirty if you want the job done right.
I'm sure there are solvents out there that'll cut through the gunk built up on the plug, but I prefer to do things but hand.
A little solvent, a toothbrush, a bunch of Q-tips and paperclip. Hot soapy water will do the trick too. When she's all done, dry and relube the threads
I'm sure this is the same route you take, and I personally haven't had the need to find a quicker way to get it clean. Maybe take a small tupperware container and soak for 30 mins in BP Solvent. Im sure that would cut and desintgrate all the gunk! Worth a try.