my 88 tii has two coolant filler caps one on the thermostat housing and one on the radiator. the thermostat housing has a nipple for the overflow and the koyo has one on the filler neck. which nipple are you guys using for the coolant overflow hose and what are you doing with the other one?

 

I'm using the overflow coming off of the thermostat housing. I blocked off the nipple on the radiator with a 10mm bolt.

 

are there any advantages of using one over the other?

 

Yea I'd use the filler neck, its the highest point in the system.

lol.. now that im thinking about it, I have no idea why thats a good thing??!?!?!