Best options for upgrades?? CPU/RPU/GPU?

I have a one way reward flight in a few weeks EWR to MNL
EWR to SFO
SFO-HNL
HNL-GUM
GUM-MNL

The return is a paid one way steerage:
MNL to GUM
GUM to HNL
HNL-EWR

I have done this multi legs trips many times and rarely get CPU on many legs except last GUM to MNL

On the itinary it shows possible CPU for EWR to SFO and GUM to MNL

I have alot of RPU and GPU. What would the best choice be?? Plus this is my first time doing this flight as a 1k status.
Maybe wait to see if I get any CPU and if not apply a RPU or GPU??
I know if I use either a RPU or GPU, they will give me the GUM/MNL leg. But from another post, I was told I can apply upgrades just to certain legs, but how do I make sure they fill?

My main concerns are the
EWR to SFO
HNL to EWR
They are the really long legs. Anyway to assure I get upgraded on these legs?? and if i can get a few of the other kicked up, that would be great.