I use this Penzoil as recomended by Cope.
http://coperacingtranscom.ipage.com/?product_cat=trans-fluid

I also have switched to DOT 5 without ant problems...yet.
https://www.summitracing.com/parts/wil-2...BSABEgLcv_D_BwE

"high performance brake fluid"

"Wilwood does not recommend using DOT 5 fluid in any racing applications." LOL