I've tried circlip pliers (why did they use c style clips and not clips with eyeholes?), screwdrivers, allen keys (and even the mrs!) to hold the circlip open, and have tried WD40 and even some heat (whilst whacking inner race with a brass drift)
Is there anything else I can try or should I just get the grinder and £150 out? Any advice would be much appreciated.
Annoyingly the joint looks OK and as I have the other end off I could have probably put new boot on from other end. That's probably not an option now that I've burnt the grease and mixed it with loads of WD40

ps - sorry if this is a stupid question. I'm a relative amateur with a sizeable welding bill

Cheers,
John