You will need the VDF for whichever calibration file you want to start with.
I'm assuming that you want to keep the stock distributer and 4x reluctor, so I'd direct you towards the stock 2001-2002 calibrations.

OBD2_03
2001 –
02 LS1 Trucks (4.3L, 4.8L, 5.3L, 6.0L, 8.1L)

I realize that the 5.7 van isn't listed, but is indeed included in this VDF.

peace
Hog