I'm sure most have seen this done,or have done it themselves but I'll share anyway. The other day I rebuilt the carb on my old ford.The carb was varnished up and no matter what I did,or soaked,sprayed... it just wouldn't clean up. So I grabbed a few feet of clear acrylic hose,a box of baking soda,and a blow gun. Looks as good as new.....maybe better ! To do it take and cut a slit in a length of hose big enough to get the tube of your blow gun in there, slip the blow gun tube in there about an inch,then tape the blow gun to the tube.Cut a 45 in the other end of the hose,tape a welding rod or ??? to it so it doesn't curl, drop it in the baking soda and go to town ! It will blow you mind how quick it gets the job done !