Ok, so I got my previous problem with the main thrust bearing sorted out (got sent an oversized flange bearing by mistake). Now, I'm installing the timing set, and I'm thinking that the machine shop forgot to send me home with a vital piece! I installed the idler sprocket by putting the insert (number 1 in picture) in the sprocket, and bolt through the washer, and bolted it to the head, went to turn it, and it wont turn. So, I took the idler back loose and it turns fine. It looks like other that what's pictured, there should be some sort of a spacer between the idler sprocket and the head? Or is that where number 3 in the picture is supposed to go? BTW, this is a 98 Frontier KA.

Please, I need some quick help!!!