Bringing In Poop/Pee Pads

Question
I have a 12 wk old black lab named "BB" and I've had her for about a month. The ultimate goal: I want her to be an inside dog that eliminates in the garage on pads. She has access to the garage via dog door. She DOES use the dog door without any problems. Initially, I tried training her in an igloo crate--that didn't go so great, she wouldn't/couldn't hold it long enough, would eliminate in the crate, and I'd have to give her a bath EVERYDAY (sometimes twice). No fun for her or me. So new training--I got a larger crate (cage style, no igloo) that allowed for the back to be dropped down. I put this cage right up against the dog door (which she uses well). At first, was going great. No more eliminating in the cage, no more getting up in the middle of the night, etc. But she's developed a NEW behavior (one week)...she BRINGS the pads (with poop and pee) into her crate. Usually adding a shred to the mix. So now I have to pick up cotton fragments, have poop AGAIN in the cage, and because she is playing with the pad...she gets a bath everyday again. So she doesn't go to the bathroom IN the crate she BRINGS it in via the pads. When poop gets smeared all over the door and dog door from being dragged in, it's never fun. I actually have to remove the door to clean it. She NEVER NEVER NEVER does this behavior when she's allowed free range of the house & is out of the crate. It's like she's either bored or mad she's in the cage and decides to go to town. This occurs almsot anytime she's left in the cage for over 4 hrs or so. Sometimes she'll even tear up the pads within 15 minutes of being put into the cage. I tried anchoring the pads with bricks, didn't work, still tore them up. I'm thinking about not puttting them down and just letting her eliminate on the linolium that the pads are on that I put out there for her in the garage. Either that or restrict her times when she can eliminate. However, I'm away at work for 8 hrs on one day...I don't think she can hold it, so that's just setting up for a failure. She's got the idea of where to go, she does it, if she'd just stop brining in the soiled pads we'd be fine. Another thing I've noticed about her, its she seems to be oblivious to stepping in her poop. There's no avoidance at all. That's my concern, if I don't put the pads down at all---she'll simply run and play in the area running in/out of her pee/poop. Any suggestions??? Help! :)

Answer
I am not sure there is a good solution to leaving a puppy unattended for 8 hours.  What you are doing isn't working, and I don't know how to make it work. She really a mid day break.  If you can't come home over lunch, perhaps a neighbor or a professional dog walker could give her a break.  

On of the flaws in your plan is that most garages have plenty of things to chew that a puppy shouldn't chew.