who uses them the most over there and what mods do you do to the standard vehicle?
M998 HMMWVs are used by just about every unit, no unit uses them most.
If you are talking about the Academy M998 I.E.D. Guntruck kit, it represents one used by the 101st ABN (even though the decals show something else, they are wrong) in late '03 when IEDs were just becoming an issue. It is an early upgrade armour kit used before ASK (Armor Survivability Kit) upgrades and M1114 Up-Arrmored HMMWVs were readily available. It woud be good for about early to mid-'04. By that time, M1114s and level-2 ASK upgrade sets were required to operate outside of FOBs (Forward Operating Bases). You will not see one like that on the streets past mid-'04.
For other upgrades to them, check the web. There were literally endless homemade armor upgrades early on. Later, they got level 1 and level 2 ASK upgrades to them as well. The possibilities are endless, depending on when you want to depict.
yes that the kit i have. most parts i’m going to use on other humvee’s and gun trucks. put i will still make an armoured m998 out of it.