In my experience, if you've gone well past the 15 degree difference between coolant and oil temps, just perform a regular flush of the cooling system using restore and then change out the oil cooler. Once the new cooler is installed reverse flush the new oil cooler just so you can get flow through those passageways which had low flow due to the original clogged cooler. As far as that reverse flush fitting goes, you don't need to get one of those. I got some 3/4" clear tubing from the local farm store and adapted that to my garden hose. All you do is remove the cover for the outlet on the oil cooler (same one that expensive fitting replaces) and the hose fits snugly inside. Other than that, definitely listen to Bismic....man knows his stuff!