Metal Gear Solid 2: Substance

Strut A - in the pump room, go to where the stairs going up and then right back down are, walk up and down them, then crawl under the pipes in front of you, then keep crawling under them to the left until you reach a big red one, crawl along the red one until you can come out on the right and the bomb is there.

Strut B - bomb is inside the room, there will be an open locker near the north door, punch the locker door down and there it is

Strut C - when you come in here, there are two bathrooms, go in the one on the right, walk up to the right mirror, and look up, there's the bomb.

Strut D - see all those black hatches on the ground? open those up, its in one of them

Strut E - go up to the heliport, run to the north end, look at the Harrier (the big jet), go around to the north end of it and crawl under the wing, there it is

Strut F - go upstairs, theirs railing all around in a box shape, go to the left side of the box, press the action button to jump over the railing, and press the crouch button to drop down in that little area, the bomb is on the wall in there, to get out of there, just climb on the boxes by pressing the Action button.