It doesn't matter where the engine is set, just don't let it turn while you have tension off the cam chains. Turn it all the way in, then release it. The problem with the oem tensioners is that cam chains, even properly tensioned ones, have a certain amount of "whip" That pounds on the tensioner, and eventually wears out the internal threads that allow the tensioner to advance as things wear. Eventually the threads wear enough that they bind. It has nothing to do with the springs. Use to everybody was replacing the springs with stronger ones. But because the worn threads were binding, the tensioner still couldn't advance. The main issue seems to be the fact that the housing is made out of aluminum, including the threads, and that is what wears due to the constant pounding. There is another trick that I tried to do a long time ago, and that was to use a screwdriver to tighten
the tensioners while the engine was running by removing the cap and sticking the small screwdriver in to turn the screw. The screw (internal part of the tensioner) was shaking so bad that it literally knocked the screwdriver out of my hand. There should have been almost no play between the inner and outer threaded parts of the tensioner.
There are 3 possible ways of fixing this problem. You can get new oem tensioners, which is the first thing I did when I heard that rattle. They are not cheap, and lasted only about 10,000 miles till I heard the rattle again.
The second, and IMO best way is to replace the automatic oem tensioners with steel manual tensioners from TOC. Manual Tensioner
That's what I did, and rode for almost 80,000 miles before a cam chain finally broke. The TOC tensioners have enough adjustment range that they will properly tension the chain even if it is worn beyond the service limit. Of course that doesn't mean the worn chain may not still break, but it should at least make it last longer.
The third way is to take the oem tensioners apart and convert them to manual tensioners. There are instructions for doing that on here somewhere. But I don't recommend it, because the oem housings are made of cast aluminum, and may crack under the stress of the constant pounding from the cam chain. The threads in the oem tensioner are also aluminum, and not very long, so it's a pretty weak design. Basically the tensioner is taken apart, all the internal parts are removed, then a long bolt is threaded through the threads that were originally used for the cap over the tensioner bolt to screw into. Since they were originally designed only to hold a cap, I don't believe they are strong enough to actually hold the bolt against the chain for very long. Some people swear by this method, but from an engineering standpoint, it just doesn't seem like a good idea to me. You could do it to begin with, see if it stops the noise, then get the TOC tensioners.