I am adjusting the length of my Hampton Bay track lights (model 672-940). The directions say to match the wires (hot wire (black or transparent), neutral wire (white wire or white marking) and ground wire (bare wire or green wire or marking) with the matching screws. The screws are easy to identify, but the wires are all silver in a clear plastic insulation. How do identify which wire to match with the appropriate screw?

Generally, this type of cord is marked with lettering on the hot wire, and the neutral has ribs running the length of it. You can usually feel the ribs with a fingernail across the wire.

If all else you will need to use a continuity tester to see which is ground, then the hot and neutral.
Touch 1 lead to the Enclosure and then the 3 leads to determine ground wire. Repeat for hot and neutral.