So if I read the phases of the attack correctly the ord exp card must be used prior to the spend defense token phase. Jut he reason I ask is due to the "while attacking" wording. Could it be surmised that "while attacking" could mean that you modify the dice after your opponent scrambles them because you are still technically "attacking" and within the confines of the attack step of the ship phase?

No.

In doing so, you are ignoring the fact that there is additional timing inherent in Modifying Dice.

Effects that modify attack dice must be done in step 3 of the attack, unless another timing is specified . This is done so with Targeting Scramblers, because it specifies during the spend defense token step , but it would have to say similar for ordnance experts to do so.

It does not.

Ordnance experts, like almost all modify dice effects for the attacker, must be done during Step 3, Modify Attack Dice.

RRG, Page 5, "Effect Use and Timing"

• An effect that modifies attack dice can only be resolved during the “Resolve Attacks Effects” step of an attack unless another timing is specified.

RRG, Page 2, "Attack"

3. Resolve Attack Effects : The attacker can resolve attack effects as described below:

◊ Modify Dice: The attacker can resolve any of its effects that modify its dice. This includes card effects and the "CONCENTRATE FIRE" command.

Ok that's what I thought. I just wanted to make sure I was correct in the usage and to keep myself from doing anything silly that might make me took like a tool. Which does happen....from time to time.....oh dear oh dear.

Just like using an Evade or Lando. Once the attacker finishes modifying dice, they can not modify them any more.