i'm currently restoring a pre lit westfield and believe the rear axle is a cortina mk2 item. i have ordered some new 8inch drums. however the standard mk2 wheel cylinders and the 1600gt/1600e cylinders are different despite looking the same on the web. someone said that the 1600e/gt had 9inch drums does anyone know if this is correct as i'm desperate to get my car brakes sorted as i don't want to not have the car finished by next summer AGAIN.

1600e is a very different car from the 1600Gt

The 1600GT brakes were basically the same as the 1600 Super -- ie P14 calipers on the front and 8" drums on the rear.

Generally these more ordinary Cortinas used single piston rear wheel cylinders that slid in the back plate and were retained by "U" clips Most models used manual brake adjusters, but some (usually those with disc front brakes) had finger and wheel type self-adjusters.

The 1600e and Mk2 Lotus used P16 calipers on the front and 9" drums at the back they were Corsair 2000 parts, also shared with Mk1 2000 V4 Capris.
Generally these used twin piston rear wheel cylinders.