Slightly off topic:
Here's the info on the seating...
http://www.vicroads.vic.gov.au/vrpdf...e/vsi%2019.pdf
There might be something in here re the gearbox mods.
http://www.vicroads.vic.gov.au/vrpdf/rdsafe/vsi%208.pdf
I think the main drama they(insurance companies included) have with g/box mods is when people cut up their cars to get the gearbox in. If there's no modification necessary to put the manual in then there should be no prob.
I'm guessing this is the case as a few insurance companies I've spoke to have mentioned this as a gripe and they usually work off road and traffic rules for a starting point on whether they take on certain mods.