Nice work! Those brackets are perfect! Guess I know what to do if I put sliders on anything else! Way easier to order those than spend the time fabricating what I did. Drill a couple holes and you're off to the races. :D
I'm surprised you were able to locate them that far forward, mine have to be a good half inch further back, maybe more. But it looks like you've got a lot more spring arch than I do, so I suppose that makes sense.
Looks to me like those brackets are at least 1/8" steel. Which makes them a heck of a lot stronger than the original shackle mounting brackets. Mine are only made out of 1/8", and the stock shackle mounts are made out of 16 gauge if I'm not mistaken.