2008 Caliber Tension Pulley

Is this thing possible to change at home or does it take a mechanics shop with a lift to accomplish? Ive tried for days to get even 1 bolt out without any success at all.
Thanks for any help.

What engine does it have?

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1. Raise vehicle on hoist.
2. Remove belt splash shield (3).
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3. Remove accessory drive belt (http://collision.alldata.com/alldata/zWindow.html?node_44348_920_0_0_) See: Drive Belt > Removal and Replacement > Accessory Drive Belt - Removal (http://collision.alldata.com/alldata/article/display.action?componentId=95&iTypeId=401&nonStandardId=1813978&vehicleId=44348&windowName=mainADOnlineWindow#).
4. Remove accessory drive belt tensioner mounting bolt. Remove accessory drive belt tensioner (8).


Looks like the proceedure is the same for all except the SRT.

I've had mechanics replace this part twice and both times it continues to rattle. Almost like the pulley isn't tight enough but its confirmed that when the mechanics install it its tighten adequately. I've of them demonstrated that applying pressure to the pulley with a long standard screw driver made the noise go away even after it was tighten. What can be the problem? I found some used car parts on AM Car Parts website Used Car Engines (https://www.amcarparts.co.uk/engine/list.html)

You can purchase a new tensioner with a new spring. Most parts stores sell them.