Indian irregular cavalry, need advice.

[red rags]

I having some trouble pinning down the 5th Irregular Cavalry (Gough's Horse), some sources seem to mix them up with the 5th Bengal Native Cavalry. Or perhaps it's me who's confused.

5th Bengal Light (or is it Local?) Cavalry also in the mix...

PLEASE explain, THANKS

ps primarily interested with the above in the First Afghan War (Cabul medal) & Jellalabad with later Maharajpore.