RC/PE6 Advancement?

I understand that this is a hard level.  I have had very little trouble with this grouping of exercises (rope climb) until now.  I am repeating the last microcycle (3 week period).  Anyway, is there any extra work (grease the groove, sets on off-days, etc.) that can assist me in getting this down?  The idea of 5 sets of 60 seconds with no rest other than the mobility, is hard for me to even imagine.

I have checked out the exercises later in this progression and don't think I will have much trouble with the next few, but this one is a bugger.  For what it's worth, I'm a bigger (>200 lbs.) and older (>40) guy.  Any help is appreciated!!

Insert some ultra slow negative reps (12-15 seconds) after the last set just after you you fall from the isometric hold.

Thank you.  I'll give it a shot!  Any more suggestions would be appreciated!

this is a good one to GTG in my experience