I have started the task of cleaning up the engine bay. Here's the bay before with 28 years of grime. I put some undiluted Tfr into a spray bottle and covered everything, giving it half an hour to soak in. Then I wiped down everything I could get to by hand, before taking it to the jet wash. I covered all the vitals with bags just in case. The results are nothing short of amazing. Going to keep going now replacing nuts and bolts and polishing various bits.