more washita confusion...

picked one up at vintage store with box and label on stone. it also has behr manning and pike markings.

my research on this has left me confused.... from 600 grit, soft fast cutter, coarse, finishing....

did a quick clean and check lapped it to confirm flat, but that was very quick work on 500 grit wet dry sandpaper

ran a couple blade on on it to test it

i don't see it as a fast cutter the way it is now. i don't feel like it would be a decent bevel setter like it is. if so it is a very slow bevel setter

i'm planning on lapping/ refreshing one side... i'd like to use it in the bevel setter range.

what grit wet dry, or SiC tumbling grit do you suggest i lapp this stone to use as a bevel setter?

any opinions comments on this?