TDS1 (1965 ish) Gear Box disassemble

[chatterbox]

Hi, Does anyone know the correct procedure to disassemble the gear box. I have removed the front and the bottom 2 shafts, but the middle and top shaft are proving difficult. How do they come apart? Some gears and bronze bushes are worn, so need to replace these... I might make the bushes, but am open to buying these and the gears if anyone has anything? thanks (I am in Australia)