OMG it is the easiest thing in the world. Get yourself a 1 gallon pump garden sprayer from your local home/garden store, the kind with a wand. Take the nozzle off (mine comes apart where the trigger is) and then use a LOT of teflon tape on those threads, and attach a spare liquid-out post from a keg to it. Done! All you have to do then is fill it with your cleaning solution of choice, pump it up, hook it up to your line, and let it rip. I ran hot oxyclean solution through mine and let it sit for about 15 minutes, then flushed it out with a lot of clean hot water. Then reattached the keg. Simple as anything. Bonus, for me anyway, was running hot water through the lines let me straighten them out from the tangle they'd gotten into.
*edit Here's a photo:
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*edit Here's a photo:
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