I have been using the cheap flat steel coilover wrenches for years and just bashing the everloving berkeley out of my hands any time the threads are gunked up. The wrenches bend, slip, there isn't really a grip on them, and overall they seem to be intended for use on perfectly clean new coilovers and that's it.
Is there something better?
I don't know that having a ratchet attached would help, but above is a Stockton Compact Spanner Wrench. I also see them with multiple (3) teeth to engage-better, I dunno.
Maybe have something cut out of 1/4" plate?
I never liked the Moroso one I own ... the one where the hook flops around and always takes two hands to attach. I like the solid one piece ones that are build for each specific size ring.
I find these Channelock #209 work the best:
In reply to Purple Frog (Forum Supporter) :
A bit of time with an angle grinder could make those channelock's perfect for whatever coilover setup you are running, looks like another tool I need.