zx6 636 engine refresh questions

[Slayir]

I am having fun refreshing my 05 zx6r engine this winter, and had a few questions. Top end of the motor is off and apart.
Head and base gaskets - does it make sense to buy thinner ones than stock?
port and polish head - worth doing?
Anything I should do while I am this far in?

Thanks

[N1K]

Yes and there's alot you can do but depending on what classes your gonna run in should stop you from doing some of them.