Real fast question... What size is the blue charge line that runs on the top back side of the engine? I am looking to make a adapter for my Water/Meth injection kit.

Just get the SD manifold.

https://ssl.perfora.net/www.superdieselperformance.com/sess/utn;jsessionid=1542aa787a64826/shopdata/index.shopscript

Why when I can make it myself ??? I am making somthing very close to that.
I just didn't want to take it off to check the size if someone already knows it.