I ordered my ERA 289 FIA with the upgraded front brakes. At the time, ERA did not offer an upgraded rear brake package. I am not particularly fast on the track, but I have found this system to be adequate for my use on the street and at Open Track events.
I replaced the single plastic brake reservoir with a dual reservoir set of cans:
I eventually dropped the third can, as I have an automatic in my car. I ended up putting the voltage regulator where I had originally placed the third can.
I got my cans from Dave Bean Engineering in CA. They carry all kinds of "spares" for British sports cars.
Dave Bean Engineering, Inc. The Official Vintage Lotus Car Parts Distributor
regards,
Jeff