Fox 38's are great forks especially when you get rid of the air spring and install a smashpot it's night and day , I've recently gone from 160mm to 170mm just out of curiosity and haven't noticed the 10mm difference whatsoever π€
Flat socket is for the air spring side , normal sockets can chew up the cap as there's very little to get a hold of , there are videos on YouTube about how to install new wiper seals without a driver but I bought a 3D printed one and it works great and less than half the price of a fox /...
I use motorex bike specific , lime green coloured stuff, great little applicator brush πͺ₯, no complaints, it's grease for a push bike at the end of the day π₯Ί