Sure grip questions

I have found what appears to be a sure grip 8.25 diff in a '77 Magnum XE in pretty good shape at the local junkyard here. It uses coil springs instead of z springs for clutch pack pre-load it appears. I suppose it's the Dana-sourced Trac Lok? I'd like to swap it out for my open diff 8.25 that I was about to put in my '69 Dart. They are both 2.45:1 ratios, so that's good for me now as I'd love the mileage with my 1-bbl /6 and A904 currently. However, in the more distant future I plan to put in a A833OD with 3.55's out back because ultimately I want to grab gears.

First, is this likely a Trac Lok and is this OE LSD rebuildable?

Second, is the carrier split for Chry. 8.25" (2.45/2.56) applicable to open AND LS diffs.

I ask these because currently Dana sells new pre-'97 27-spline Trac Loks that are rebuildable and use ALL ratios, mentioning nothing about the carrier split I have heard about. Or are these only features of modern Trak Loks? Thanks