would this weird gangplank build work?
so I was thinking of trying a weird sustain max CDR gp build. Thoughts?

The ap jungle item is really what sets my build apart. I'm getting manamune simply because I need a mana item on gp (one without CDR since jungle item already gives 20%). I'd get trinity force but then I'd have to go trail blazers.
So the idea behind this is mostly trying to capitalize off of spirit visage healing bonus from eating oranges. Also having some ap works well on gp's ult along with max CDR.
Would getting ap masteries be good? Should I get hybrid pen runes or just armorpen?
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Instead of Randuin's?