I do like to use the ability modifiers from a more recent edition:
Making A Character
Below is a Saving Throw guide for each class.
Or, you can just put some of these guys in your regular-old D&D campaign. I won't mind.
METRO COP/CIVIL PROTECTION
1: The loot is unusable
2-5: Standard armor + weapon and 1 ammo
5-10: + item below
11-16: + + 2 items
17-19: + 3 items
20: great item
Pack of cigarettes