Static timing is set on no.4 cylinder on Betas. It is easy to get it 180 degrees out! I would recommend:
1. Take oil filler cap off so you can see No.1 cylinder (waterpump end) exhaust cam lobe
2. turn engine over until crank pulley marker lines up with static 10 deg before TDC mark (on cam cover usually)
3. Check exhaust lobe position on No.1. It should be pointing downwards at final stage of closing valve. This means No 1. is on the "overlap", exhaust closing inlet opening, and No.4 is nearly at top of compression stroke about to fire.
4. If No.1 exhaust cam lobe is pointing straight up, No.1 is on firing stroke, so keep turning engine over until you come back to 10 deg BTDC again on No.4
5. The rotor arm should now be directly pointing to No.4 lead on the cap. On most Bosch distributors there is also a line where the cap seats on the base in the same place that you can line up the rotor arm with.
6. Note position of dizzy in block, undo M8 nut and withdraw!
7. Note plug lead order before removing all leads! Firing rotation is clockwise and lead order is 1-3-4-2
8. When refitting line up rotor arm with line on dizzy first then insert, making sure rotor arm is held in place so it does not move.
9. When inserting make sure shaft splines engage in aux shaft driven gear. Don't forget gasket on base to block or you will have an oil leak....
10. Check static timing is 10 deg BTDC, rotor arm pointing to No.4 lead, refit clamp & just nip up bolt.
11. Re fit cap & leads, vacuum advance etc. Start & check timing with a strobe.
Easy.....