Just offering advice, that for tuning/modifying an almera engine and gearbox you'd get more definate answers from people who have and modify almera's.
There's only 3 ga16 conversions I can think of at the most, and I've only seen 1 of them, and the others not even photo's.
None of these have had modified engines and also used ga16 boxes.
So trying AOC would probably give you more definate answers as chances are if it's worth doing, they'd have done it.