dnd 3.5e – How does Maximize Spell Like ability feat affect items that boost your damage?

Assume a level 9 warlock has following damage dice:

-5d6 from base EB

-2d6 from Mortalbane (Feat, does not require CL)

-2d6 from Greater Chasuble of Fell Power (Item – Caster level 9th)

-2d6 from gloves of eldritch admixture (Item – Caster Level: 3rd)

Maximize spell like ability feat mentions:

The spell-like ability you wish to maximize can be chosen only from
those abilities that duplicate a spell of a level less than or equal
to 1/2 your caster level (round down), minus 2.

If this warlock wanted to maximize their attack using all of the dice above, would he have to re-calculate the Maximize Spell Level according to formula ((CL/2) – 2)? If that is the case, would you take the item that requires the highest CL or add up all the spells that requires CL (1 for EB + 9 for Chasuble + 3 for the gloves)