Max Spell point on GS Item

[Zordar]

Is 150 the maximum spell points I can add to a green steel item, bracers for example?

[BurningDownTheHouse]

If you mean besides the wizardry VI, the answer is yes (double for sorc though).

[Griphon]

Don't forget that making a +3 Intel/Wis/Char boosting item also boosts your SP total by a smidge too.