[Amps] some more tetrode questions

[Ed Heimbach]

A few weeks back I asked about reconnecting a 4-1000....
 Currently the amp is connected GG, both the screen and the grid strapped directly to the chassis.
Many differing viewpoints were offered on how I may increase the output of the amp, easiest being to raise the plate voltage.
 However, I have no budget for a new power supply.
 I believe I shall try this.
 Disconnect screen and grid straps,then place a 650 pF, 18kv doorknob cap between tube pin and ground.( why 650pF? because I have a bunch of them).
 Next is to connect bias and screen voltage at the tube socket. 
I will use a regulated bench supply for the bias, and a spare Hi volt supply (completely separate from the plate supply) for the screen.
 Plate supply is variable, up to 4.5kv. at 3A (big iron from old A.M. station)
Cathode drive will be retained.
 Any comments? Any obvious faults to my logic?
73, AB3HT