Narrowing 8 3/4 details

So I decided to narrow an 8 3/4 for my Dart project, I got the housing off a C-body for $60 at the junkyard and a pair of stock A-body axles from another FABO member for $50. So far so good, but I have a few questions:

1) When shortening a driveshaft, does it need to be re-balanced?
2) Can I clock the new spring perches using the old ones or do I need to check the pinion angle?
3) Has anyone seen the following musclecar episode? Tommy narrows a housing without a jig! Is this wrong or can it be done? musclecar