The hydraulic system should take up the extra clearance and give the same biting point BUT.....
if the slave cylinder reaches the end of its travel and pops out of the end you will have a puddle of fluid in your bell housing and no clutch realease 
Also.. if the gearbox input shaft isn't long enough the driven plate might not engage the splines and/or the nose might not engage with the spigot bearing.
I think the "concentric" clutch cylinder on Omega B has a positive stop which would prevent it popping out. It would prevent any clutch action beyond the stop, though.
all of the input shaft choices are the same length ( apart from gearboxes for CiH )
also apologies for not posting up all of the dimensions - I'm having a mare of a day - someone drove into the back of the Holden this morning
Sorry to hear about the smash mate, hope all is ok?
And the 3.2 clutch is unique to the 3.2, main dealer only and made of cheese (for my abuse anyway), tractor one is different afaik.
If a tractor one will fit, the result as being diseasal means its potentially beefier