Dead Space Maxed Out Achievement

Alright, so, I started out on Hard, beat it on Hard, noticed the cleared out thing, seen that it went to the beginning of the game(On Hard difficulty) Now, I want to get the uh, Epic Tier 3 Engineer achievement, but also the Maxed Out achievement, so i'm gonna go on Impossible, but, I need to know, if I can beat it on Impossible, have almost enough nodes put into the armor / weapons for the achievement, then possibly back track to like medium with the same guy, anyone know if that can happen? If I'm making absolutely no sense, I understand, I can try to explain it again.

Thanks

DBakertron 5000.

You have to play again on the same difficulty that you beat it on the first time to have your inventory and nodes carry over. I beat it on easy the first time to get most of them, an currently going to run half way through a second play through on easy to get the rest, then will start a third game on impossible to finish off the achievements.

For you, it sounds like you'll have to go through some of Hard again to keep everything and get the maxed achievement.