197 from Portugal - starter kit

Hello all,

Just got my Clio 197 '06 model to replace a track-day car I owned (other brand) and got tired of it.
The plan for this new car is to make it capable of going to circuit for fun, but still be driven on public roads.

I know I have a lot to read here, but would like your help on setting the starter kit on my car.

What it already had when I got it:

18" wheels Hunter brand and lightweight
Michelin Pilot Sport 5 tires
Brembo HP2000 front brake pads
Ramair air filter
Scorpion exaust without center muffler
HR lowering springs with CUP(?) shock absorvers

Need to service it, in order to use it without any fear.

Plan is:

Original oil filter
Motul 300V 5W-40
Castrol SRF brake oil with
Hell braided brake lines

Need some advice on intake to use. Would go for the ITG intake but my car is LHD. Do you believe the fitting is possible with some small adjustments?

Will upgrade to DS2500 brake pads as these will be gone. Is this OK or you have better option?

Any good option on spark plugs that are a good fitting on this engine?

Should I keep the 18" or better find a set of 17" rims?

I have the blue HR springs. Any better option still capable of daily use?

What gearbox oil you recommend? It shifts like butter and want to keep it that way.

Thank you all for any help you can provide me.

Cheers from Portugal