Shouldn't be to much of a work out.
HA! you haven't done much honing have you
I have done many engine blocks. I figure thats about 2-1/2 small block Chevy's worth lol. My arm's always get sore. But it's good for you!
I think you for sure need to start with the 240. It will leave hash marks. You can lessen them by pulling slower. You'll want to start faster to get going. See what the finish looks like with the 240. I'd guess it will look smoother with the 500. The berry hones are aggressive. Don't stay in any one spot long. I have over size a cylinder bore to knurl a piston to fit. You can cut 3-4 thousands pretty fast. Honing stone's are way slower and easier to keep from screwing up. The berry's are way faster. You are not fitting a piston so you have more leeway I'd say.
Looks like im late but i have finished a couple of mine with 220 grit stones. With black powder i see no real reason to polish the bore too much