For the Consett/CLS allocations, I'd go:

E400 (6338-51)
- 3x Consett X30/X31
- 2x Consett Spare
- 9x CLS X21

SD G2 (6331-33)
- 3x CLS (spare or extras for 21 if needed?)

B5TL (6308-14 & 6334-35)
- 7x Consett X45/X71/X72
- 2x Consett* X45/X71/X72

*Ex-dealer stock, 6338-39 allocated instead if not needed on X30/X31

SD G3 - 7x freed up for other use