Going to do a full bleed front and rear on a R53 JCW. Anyone know the total brake fluid volume?

 

Having installed more than a few kits along the way I'd say you'd be needing no more than a quart. Two of the smaller 6-8oz bottles should do you fine. Not like there's that much fluid in there really. The pistons are not full of fluid, they're hollow and the fluid pushes on the flat size requiring only a few cc's of space.