Armor Check Penalty Reductions

[cartejos]

Given: Feats don't matter as much as normal
Given: The Character will be using a bastard sword, full plate, and a tower shield

What are the best ways to reduce armor check penalties for both?

Greater Heavy Armor Optimization is a -3 to Full Plate
Mithral is a -3 to both (Steel Tower Shield made Mithral)

That's a 0 ACP on the full plate and a 7 on the tower shield.

In 3.5 is there further ways to mitigate the Tower Shield? Perhaps more ways to reduce them both at once?

Edit 1: X5/Vengeance Knight 10
Masterwork Full Plate
Mithral Tower Shield of Nimbleness
0 ACP except for swimming
Or 1 acp if Nimbleness cannot be put onto shields

[BowStreetRunner]

Don't forget that Masterwork (http://www.d20srd.org/srd/equipment/armor.htm#masterworkArmor)(and by extension all magic) armor and shields have their ACP reduced by 1.

The Nimbleness enhancement (MIC 13) on armor reduces ACP by 2 and increases max dex bonus by 1.

EDIT: The Guerrilla Warrior feat (HoB 97) lessens the ACP on light or medium armor by 1. I had almost discounted this since you are talking full plate, but if you are using mithral full plate I believe that changes it to medium armor.
Also, the Dread Commando PrC (HoB 103) has an ability that lowers ACP by 2 points at 2nd level, and another 2 points at 4th level.

[ShurikVch]

Vengeance Knight PrC (Champions of Ruin): Armor Training CF will reduce ACP for both armor and shield at the very 1st level by 1 , at 6th level - by 3, and at 10th level - by 5
(Note: this PrC required LE, NE, or LN alignment)

[KillianHawkeye]

Don't forget that Masterwork (http://www.d20srd.org/srd/equipment/armor.htm#masterworkArmor)(and by extension all magic) armor and shields have their ACP reduced by 1.

The adjustments for mithral already include this, because all items made from mithral are automatically masterwork.

[Darrin]

The adjustments for mithral already include this, because all items made from mithral are automatically masterwork.

I often use darkleaf instead of mithral (cheaper), which doesn't automatically include masterwork quality. So you can pay a little extra for masterwork darkleaf and reduce ACP by 3.

You can also add the Hellforged template (DMGII) to improve the ACP by 1 (minimum -1).

If you add the Nimbleness property on top of that... I think the best you can do is a 6-point reduction.