Sorry to be sucha stick in the mud, but I have a few pointers that might help you out?
Mohawks, and pretty much all the tribes that fought in the French-Indian war, would go into battle bare chested, with often just a loin cloth. Some did wear fur/skin breeches though, that went midway up their thigh.
The Iroquois peoples were heavily pierced. by this I mean they had many many piercings in their faces and ears.
Also, Mohawks didn't wear feather plumes/head dresses usually (looking at your latest screeny). Instead they did their hair in a particular fashion (exactly like in your signature) as did most of the tribes (each having their own particular style). However, the other tribes of the Iroquois did use feathers in their hair, but it was tied into the knot at the back of their head and not the front, like western plains war chiefs.
Here is a good picture:
Also, the bow had almost entirely died a death in the tribes now, with only the NA's on the western plains still using them during this time period. All of the stone arrow makers had pretty much died, with the young warrior elite preferring the musket or rifle. This was a major downfall for the Tribes as they couldn't produce their own powder, creating a heavy reliance on the English/French traders. Often tribes would sell huge swathes of land for powder (and rum
) when it was a long winter or they had not bought/traded enough food for the winter, or they had traded all their furs for rum (which was most often the case), leaving their tribe short handed.
Iroquois ridin to war on horseback is another no-no, as the land they inhabited an fought in were mainly forrested areas.
A good artist to look up for good and accurate Tribal references is Robert Griffing, some of his works a stunning and highly detailed.