So I'm reassembling the engine following a catastrophic timing belt failure and am down to putting together the accessory belt idlers, etc.

I can't find any torque specs on the big idler above the crank. In fact, it doesn't appear at all in the drawings, so I wing it and start torquing all the bolts to 15 ft-lbs since everyting else is 15 and snap! The small bolt at the top mount position in the idler breaks off in the block (which of course down in a hole and it looks like I'll have to remove the timing belt, water pump, and everything else I just put on). I do some research and good news! I can just toss the whole idler assembly since the belt routing has been revised at some point and it's no longer used. I guess that's why it's not shown in the drawings...

Which brings about some questions.

What is the difference between the new and old tensioner assemblies? How can I tell I'm buying the right one at the auto parts store (I'm not going to the dealer for this one...)?

What is the new belt length?

What about the hole left by not installing the idler? There is a rather large stretch of timing belt left out in the open (12" +) that used to be covered... Is there a plastic cover available for this now from Audi? Should I mount the old idler bracket just to have things covered up?

Part numbers?