Reverse Shackle job questions

[Jim <junglejim@domain.elided>]

To all,
I was looking at a catalog for a reverse shackle kit for my Scout II.
I have some questions, and I hope I am not the only one out there with this
question.  I don't feel bad for showing my ignorance, I plan to steal as
much knowledge from all you handy folks out there that I can.

Anyways, the catalog listed prices (a bit steep I thought, but what do I
know) for a kit, and a kit w/o drive shaft.
Could someone explain what is involved with this type of job, and what it
does for my Scout (or will do)?
I am mostly confused on the kit with drive shaft.  I have (I think) a front
drive shaft already, but do I need a different one if I install a Reverse
Shackel kit??
Thanks in advance.

Jim Coyle
'76 Scout II
345v8/tf727