Hmm, that could be an interesting project, but plan on the long haul.
Personally, I would be inclined to start with the best reverse Okeetee lines I could find with the intention of crowding out the blotches with the expanded borders. The hopes there would be that normal colored (meaning NOT amelanistic) forms from this line would have those expanded borders showing up as black and obscuring the normally red color of the blotches with black.
Then go for the background color heading towards white. You might have to have parallel lines running with each having a different goal, and then when you got each line as close as you think you could get, then start merging them, hoping you can get the best of each line showing up in subsequent generations.
Throwing in Anerythrism, of course, could be a big help, but Anerythrism seems to cover over the normal colors rather than actually remove them. If you remove the anerythrism the coloration will still be there.
I actually had a line of Anerythristics that were notable for having very solid black blotches to them. Wish I could remember what line they came from. Seems to be that it was not something I would have expected from the normal colored lines it came from. Maybe it will come to me sometime and I'll make note of it when (if?) that happens. I might actually have pics of it somewhere in this personal forum I have here.
But like I said, plan on a VERY long haul with a project of this nature. With the understanding that genetics (and Murphy's Law) might be fighting you tooth and nail the entire time.