First Design, made by slapping down arms 7 & 8 and the multibonder for the N=3 stick input. Working backwards from the final input, 3 every 6 pipelines for 1/3 of the output seems like the obvious way to go here.

The Top 1/3rd pipeline is kinda bad, needing more arms and track than feels like should be necessary due to geometry and timing issues, that I'm reasonably sure would need a redesign to fix. 

6P saves 15g: With 1P the triarm grabs the output trying to grab the next input and needs to be a 2 arm triangle trackloop instead, hence the wait at the end.

The rest of the solve feels pretty decent however, working on a clean every-6 loop. Guessing min G for 39C will be about 100g cheaper than this at around 350g, pretty much there for the taking all on the top 1/3rd pipeline, and also maybe saving a couple more arms/bonders: I re-use 0 bonders in this solve.