[Amps] pi filter QBL 5/3500

[PE1E]

1.
If I build a plate output pi filter ( > Cin 5-300 pf 25Kv var.vacuum > tapped coil .3 " copper pipe > Cout 15-1000 pf 5 Kv var.vacuum ) for my QBL 5/.3500 HF amp ( Va 6 Kv , Ia 1.1 A ) in statu nascendi ( 160 mtr - 10 mtr ), what 'd be the output Z matching range , i.s. is a separate tuner still required in order to tune out the antenna reactance or could the output pi filter does this job ?

2.
Could I replace the pi filter .3" copper pipe coil by a roller induictor ( 3 mm copper pipe, close wound, 32 uH ) i.e. could this ( very heavy ) roller inductor withstand > 4 Kw RF out ?

What is the impact of ( it's a long time ago I learnt ) a close wound inductor instead af of spaced wound conductor on the pi filter's performance ?
Which one has the least loss in a pi filter ?
( In some commercial amps I see a close wound 3 mm roller inductor, in other types I see free hanging  fixed spaced wound 5 mm tapped inductor ).

3.
I'd build the amp cf the G2DAF concept.
Does this have an impact on the values of the pi filter components ?
( I intend, as stated above, to use Cin 5-300 pf and Cout 15-1000 pf ).


Thanks for any help or reference.
Peter, PE1E