If you're having problems with the pre-made FitMetaknight.pac files I included, or if you want to easily add the effects to a PSA, this should help.

Take a clean (or PSA'd) copy of FitMetaKnight that works in your copy of the game, and insert these files into it.

The 4 textures replace the default textures within FitMetaKnight.pac

EffMetaknightMachTornado.mdl0 goes into ModelData[19].brres
EffMetaknightSwordFlare.mdl0 goes into ModelData[12].brres