If this is a 2SW2 - you can try to reinforce. 2SW2 is crossed over at 100Hz; 2SW at 70Hz). I would not do so on a full range Model 2, where the cabinet "ringing" is part of the Helmholtz resonator, helping the speaker to reach c.40Hz. There were people who attempted to reinforce the Model 2 and while the sound appeared "tighter" and more controlled, it lost most of the lowest octave.
The amp rebuilt looks good, even if the little resistors "forest" on the left could have been sorted out on a small pcb. Hopefully, they sound good.
Arthur