I didn't worry about the tensioner guide since it's in the lower part of the block. I loosened the old tensioner, but didn't remove it, to change the upper guides, then left it loose while rolling in the new chain. By loose, I mean the bolts were backed out about 1/2 way, that allowed just enough to slip off the left cam sprocket.
Upon finishing the new chain roll in, it appeared the chain was one link short, removing the old tensioner allowed the chain ends to meet. Once both ends were connected I installed the new tensioner with a new gasket. It took every bit of oomph I could muster to compress the new tensioner AND hold it in place while starting the bolts. This might take a couple tries as it is kinda tricky getting the tensioner rod to mate just right on the guide pad - looking down into the crankcase once the old tensioner is out you'll see what I mean.
Once the chain is all the way in, connected and new tensioner in place, be sure to roll the engine through two complete revolutions yet again. On a side note, I found it took something like 6 revolutions to bring the new master link back to the same position it was when installed. Remember this chain is 6 feet long.
Hope this helps.
'73 280SEL 4.5 (9/72)- RIP
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2012 VW Jetta Sportwagon TDI...at least its a diesel
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