Adding Trailing Zeroes

I need a macro to do a comparison between two spreadsheets, and one part of it is throwing me, as I need to compare apples to oranges. Here's the situation:

Sheet A has the data noted like this:
PAC
11000
11100
11500, etc.
All data should have 5 digits, and my numbers range from 11000 to 87028, though quite a few are skipped.

Sheet B has data like this:
PAC
110
110-CBS
11000
11100-ING
112
11500-L

How can I change sheet B to:
1) Drop off the dash and anything following?
2) Add trailing zeroes to make sure all numbers are 5 characters in length?


Thanks in advance for any help. I don't have any code to poste on this because I'm just about to start writing it, but need this part first.