First off Pepsie contains more phosphoric acid than coke. I prefer rum with my coke, spiced or dark :
I am trying a produce called Evapo-rust which works by a selective chelation process
www.evaporust.ca tel 416-543-0717 which is avaiable at most automotive shops.
The product works pretty good for soaking ferrous items overnight
Roberta
AKA Universalgrl