Sanding and polishing the Block
It will take ALOT of time to accomplish it took me 3 months to do the LT1 block, now aluminum LS1's are a softer metal, and might gain some time vs the iron, but none the less it is a tedious job....Most machine shops will tell you if your gonna have machining done to the block, they wanna do it first at risk of knicking the finish, then some powdercoaters are gonna say they need it first, cuz the heat from the oven might warp a freshly machined cylinder...
I would say pick up some spare parts from a junk yard or somethin with intricate places on it, and practice on them....
I did the top front of the block by the heads and water pump where you can see with the hood open. Doing all the rest would be a Mt. Everest accomplishment. I don't want to do that because I'll end up doing the transmission too and so on. Then I really wont be able to drive it!
Just do the front strap you can see by the wpump and heads.

