Looks good! If only those fence posts were metal just as a secondary heat sink. haha
I was gonna ask if they came pre thermal pasted then read that they did. Theres one thermal paste out there that works a fair amount better. I think arctic something. There was a review when i was looking up water cooling for CPUs. It was pretty constantly a few degrees cooler every time. Its more expensive but barely i think 5 bucks a tube and you might need 2 tubes.
Also you could probably get some better fans for cheap too. They should be ones designed for pulling air through a radiator. Which those ones probably are, just an "optimal performance" thought.
Ever thought of puttin a single fan on each end of the posts blowing in?? Just another random design thought