I have no idea how to read the multiple hits table for full auto shots from guns.

How the hell do you read it?

The dice tell you where the first hit is (reversed result of the hit roll applied to the hit location table). Then look at the Multiple Hits table, take the row that begins with the body part your first shot hit and work your way across it until you reach the number of shots that did hit.

For example:

Alex Arbitrator has a bad day, which means that the punks he fires on from his trusty Rhino have an even worse one. He's using a standard issue Heavy Stubber, has aimed for a round and now lets go full auto on the leader of the riot he's supposed to suppress. He is below half distance (60 metres), so he gets an additional +10, for a total of a +50 bonus (Short Range 10+Full Auto 20+Aim 20) to his BS of 40. He now rolls a 41, which obviously hits with 4 degrees of succes (49 points below his BS, every full 10 points are one DoS). Reversing 41, we get 14, which means the first shot lands on his enemy's right arm. Looking at table 7-6, we take the "Arm" row and see that his second hit lands on the arm again (we'll assume this again means the right one since that's a little more probable than the shot miraculously wandering to the other side of his body), the third hits the body and the fourth hits the head. All in all, this will likely result in a really dead enemy.

The way I see it:

Since you score a success you have a hit, so the first hit should be if you roll equal or less than your BS.
So if we take a BS of 60% including all modifiers in both examples:

Semi Auto:
Joe rolls a 59 so scores a single hit
Joe rolls a 40 and thus scores 2 hits
Joe rolls a 20 and thus scores 3 hits

Full Auto:
Joe rolls a 59 so scores a single hit
Joe rolls a 40 and thus scores 3 hits
Joe rolls a 20 and thus scores 5 hits

This is how we use it...

Cifer seems to have hit it dead on right, and explained it well.

And I am obviously to blind to read the post properly...that or to tired.
I shall whip myself 20 times...