Fly wheel Question?

Hi im about to change the clutch on my 2007 Vrs PD Diesiel and have a few questions

1. Does it have a duel mass fly wheel ? and if i does does any one know the back lash tolerance?

2. Do you need to check through the inspection hole to see if it has either a LUK or SACH flywheel iv been told you have to match the same make clutch up to the flywheel is this true?

3. If it has a duel mass flywheel is it worth changing to a single mass?

Any help is appreciated  :think: