optima battery fitment

No. I had to modify the "wedge" that holds down the edge of the battery, since the optima is slightly smaller.

I glued a piece of ABS plastic to the original battery hold down clamp, and also used machine screws after the epoxy dried. Once dry, you can screw it down as you would with the OEM battery, except that the Optima will now be snug.
 
optima makes an adapter
http://www.performanceproducts4trucks.com/productpage.aspx?cid=11&sid=98&pid=104464

scroll down the one you need is called the puck adapter.
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