i was going to by martin J's and then he sold it so i spoke to scotty about doing the same to mine.
The t56 is a very heavy box, there are about 15 variations, but all roughly weight the same.
Mods wise its the usual, t5 housing needs adapter plate, prop need modding for spline output and shortening, new clutch, custom cradle, and also hydrualic conversion.
Still a reletively cheap conversion
I however went for a tremec TKO 600 box, same as rods.