Grunt was one of the first two Joes I ever owned. He was iconic for me not only in that way, but the fact that his card artwork became the symbol for GI Joe for a while. I even had a sleeping bag with his picture on it. I was disappointed in the figure Hasbro made fro him in the Senior Ranking Officers pack, so I made my own.
Here is a side-by-side pic with a sleeping bag like the one I grew up with:
I have two different sets of lower legs for him. One is similar to the original figure's boots and one is a set of jungle boots, which I actually like better for him.
Yes, the knife is removable, a trick I learned to from Spin Doctor's Grunt custom.
His head is the dark haired Joe Trooper from the TRU Firefly Battlepack with repainted hair and eyebrows. I chose this head because it reminds me of the original figure... which looks like Fred Dryer and NOTHING like Grunt's longer blonde-haired comic book appearance.
I also had to move the grenade up on his webgear to not get in the way of his M-16. Although the camera flash makes them look different, the brown paint on the figure nearly matches his webgear.