Astra MK 4 Valve/Tappet replacement - mishmash
Are there any specific tools available to make this job easier i.e. minimising opening up the head? Its a DOHC engine 16V 1.6 Ecotec. I've only got trouble on one cylinder - Would the valve seats for this need to be grinded in or is it all supposed to be a snug fit where I don't need to chanage anything?

Please help.
Astra MK 4 Valve/Tappet replacement - mishmash
please can someone help on this? thankx