Well I just finished rebuilding the calipers and master cylinder on an 81 xj750 seca the master cylinder has a fill tube on the side of the brake fluid reservoir, but no window to see where the fluid level is at. Is there an easy way to add fluid to the reservoir while bleeding the brakes and how does one keep from overfilling it ? If there is an existing thread already covering this question I would appreciate someone posting a link. Oh! and by the way, the master cylinder rebuild kit that Chacal sold me fit perfectly.