Thanks for the compliments......it took a few weeks from start to finish..
I used all kinds of home made devices to get into all the tight nooks, soft rounded wood sticks with various grit paper seemed to work the best as it would not scratch the metal.
the majority of the prep work was all done this way by hand.
i was fortunate that the compressor had very little casting flash. ..and the quality of the aluminum was great as i encountered no pitting and a great finish