Doesn't matter a whole lot what you use to block the
BUT MAKE DAMNED SURE YOU BLOCK ...AAAALLLLLLLL.....
2x4's are sufficient for smaller towers, up to 50-60',
but do not fail to block the upper section before you
get your toes and fingers in there. even a 1" slippage
could pin you in a very awkward position.
Else, your cw may be choppy...and your baserunning
may result in you being called "toeless Joe"
Also, I would strongly recommend a buddy system, not
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