Trichlor is nasty stuff. Carcinogen and ozone depleting. I use brake clean on rag. Then blow off lint that the rough surface catches. Then wipe again with wax and grease remover. Blow off yet again. I also use an industrial primer. I got a couple of quarts from a supplier. It was red oxide and I brushed it on. I think it was a Rustoleum product. Seemed to work great. Did this on last two engines I built. The 440 was done 10 years ago. Although the engine is now disassembled, it still looks pretty good. My hemi was painted last year so no run time on it yet.