The old rules were in Imperial Armour: Volume 3.
Basically they were 6 point guardsman in a unit of 6-12 and are the same as they are now in every way with the following options
-Take a sergeant equivalent for 10 points
-Take frag grenades for 1 point per model
-The sergeant can take a pulse rifle for 3 points
And finally, all imperial troops fighting the auxiliaries always hit on a 3+ in combat
Mining work gangs:
1 gang leader, 5-18 miners 0-1 ogryn
Gang leader: 12 points (A BS4 Seargeant), no armour save
Miner: 5 points, basic guardsman profile, no armour save, equiped with las pistol and close combat weapon
Ogryn: 25 points, usual profile with no armour save
-1 miner can take a meltagun,
-Another miner may take a demolition charge
-Gang leader may replace his pistol and CCW for a lasgun, shotgun or autogun for free
Both are troops choices, and both are pretty bad, good for a narrative though.