Nothing against the AA kit. But im in the process now of swapping a late model nv4500 in place of my 700r4 (more work than your swap) you can run you current master cylinder and the late model slave cylinder by using this hose.
https://www.summitracing.com/parts/ear-64191936erl and these 2 adapters.
https://www.summitracing.com/parts/ear-ls641001erl https://www.summitracing.com/parts/ear-592054erl. on it just an option.
Also know that the 2001 2500 hd may have a slightly taller top shifter plate and shifter knub and this will plache the shift handle and knob higher. This is because the hd of that year had a factor body lift. This is what i have been told. And i have not completed my swap yet so take my info with a grain of salt.
I get external slave is easy maint but a quality internal slave should last a long time usually longer than the clutch and just replace it when you do the clutch as maint. My daily driven chev cobalt has internal slave and im on origional slave and clutch 15years and 265,000miles so far.
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