I’ve bled my old Hope C2’s OK, but I’m not too sure about how much fluid to put in the reservoir before screwing the lid back on.

I just filled it about halfway, but isn’t there going to be a head of air trapped above the fluid afterwards?

There was some magical way of screwing the top on, whilst winding out the adjustment so it had no air trapped. (think it involved wrapping stuff round the lever to catch some spillage) – if memory serves me right you screwed down the top whilst holding the adjuster with more brake fluid in than you have at the moment.
Then pushing the pistons out with the bleed nipple open and bleed tube attached and the adjuster fully wound out. Having said that I haven’t had C2s for about 6 years now, so could be talking a load of bull 😆

I that kind of like brimming the reservoir (and letting it spill when the top goes back on), then bleeding off some fluid once the system is sealed?

sounds about right, don’t think I had to absolutely brim the reservoir but something like that!

Do the screw the cap back on while holding the adjuster still (so it unscrews) and then usually blows a small amount of fluid out at the caliper to allow it to retract properly

Ah, I understand what you mean now.

Cheers for that.