Looks like a winner! It might be a good idea to run the TSP solution in the cooling system for a few minutes to degrease the entire water jacket, then flush with clear water for a while. The oldtime heavy duty cooling system cleaners were a combination of Phosphoric acid to dissolve rust, and TSP to cut greasy deposits. The 2-part DuPont cooling system cleaner in the double-ended cardboard tube had an acid/degreaser in one end, and a baking soda neutralizer in the other. I haven't seen that stuff in years, but the chemicals it contained are still available.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!