Your first photo of the machine shows the tensioner bracket mounted upside down and the tensioner assembly is still in your collection of bits. Below is a rough out of what we're looking for. Note also from my photo that you're missing the little spring plates and attach bolt (I've got them clamped with a zip tie in my photo. Have you got these spring plates in your collection? If not I'll send you some.
We need these spring plates fitted to be able to continue with assembling the tensioner. Also, we are going to need to find out if you have the stepped bush that needs to be in the slot of the tensioner arm to allow it to slide. Probably best if I draw you a sketch.
