By taking 2 Kt66's out from the Marshall Vintage Modern 2466 100w head to make it 50w. Will this in any way do harm to the head?

Epiphone LP, SD Alnico 2 Neck, Pearly Gates bridge, Ibanez S series.
Marshall VM2266c, Marshall JVM410H + 1936c, Marshall MG100DFX
Vox Tonelab ST, Boss GT-8, Korg Ax1500g.
MXR Classic Distortion, MXR 10band EQ, Dunlop Crybaby
From what I've heard, I don't think so...

But don't do that, I don't know for sure.
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I know that, but will it do any damage to the circuit, components or even speakers?