Dealing with the rust - flush with Thermocure?

how do you XK owners deal with rust in the cooling galleries and ports?
Having removed teh head, I can dig out most and the worst of the visible rust and crystal build-up, and have been recommended to rebuild and run the engine with Thermocure Radiator Flush… then flush accordingly…

Anyone have an opinion about this?
Any other cool ideas (no pun intended) ?
What about chemically dipping while the head is off and on the bench?
Cheers, Christian

I treated a badly corroded Mk7 head with that product . I used a stronger solution than they said because My system was over what they recommend for the one application . Its not a miracle worker but it did get a lot of crud out. I think the longer you leave it , within reason , the better it is .

Thank you for your feedback Kenny.

My head was heavily stained by rust, so I inverted the head, blocked the water outlets, then filled the water jackets with oxalic acid(about 10% soln), as available in Home Depot in a product called wood and deck cleaner, or something to that effect…did a marvelous job and is safe for aluminum. I used it in the block, too.