Interesting stuff Danny, keep the pics of progress coming - you've got my attention!
I'm also in the process of rally rim refurb. Doing some test paint sprays [2 pack] atm on a junk rim.
There's a company here in Perth, Australia [Able Westchem] that has a product called rust evaporator which may be the same or very similar to evaporust. Must get some and give it a try.
http://www.westchem.com.au/sites/westchemcomau/assets/public/File/RUST%20EVAPORATOR%20WC1003%20-%20INFO.pdfI'm prepping a couple of other rally rims for a full test run. So far I've stripped all the old paint off [except for some 'pooling black'], ripped the surface of all scale with neat hydrochloric acid [very fast!!], heavily flushed with water, immediate compressed air dry then treat for 30 mins with por15 metal ready followed by another flushing and compressed air dry.
The metal ready leaves a nice, slightly blackened phosphate surface that's free of flash rust.
I'll be posting up pics of my progress soon, but might be a wee while as I'm also in the process of refurbing some Momo Star wheels.
Having to rehearse my spray technique of 2 pack c.o.b. AM94 extra course aluminium to get my flip/flop/face just right.