Although I had converted the front drum brakes to disc brakes not long after purchasing the Bugeye, I had not been able to find the proper 3/4” piston version that would have been used on the 1098 cars. My dad was able to source one from California during the previous winter, and in early August he installed it. He ordered the new master cylinder from Gerard Chateauvieux at Gerard’s Garage http://www.gerardsgarage.com Both the clutch and the brake master bores are 3/4″. The push rods are also shorter than the originals. More information is available from theses two pdf files:
BrakeCylinder.com– Midget Sprite Spridget Master Cylinders Disc Brake Upgrade
After bleeding the brakes and clutch we did end up with improved brake pedal feel and stopping power. He removed the entire pedal box, installed the new master and then re-installed the pedal box.