The simple answer is NO!!!

It is stated quite clearly in the second .pdf "QA standard plan sheet 1 of 3 (General Notes to the first .pdf)... For instance, look down within the .pdf at third column from the lower left-hand corner where it is written:

6. Plastic Hinge Protection

Now go down to "F." Where it states this:

Welded, bolted, screwed in, shot-in (Powder Driven) attachments for perimeter edge angles, Shear studs, Exterior facades, Partitions, Duct work, Piping, or other connections shall not be permitted within the plastic hinging zones.

This is just my opinion but if I were you, I WOULD LEAVE THAT ENTIRE ZONE ALONE!!! Or else risk being back-charged to death for all the procedure you will have to comply with in order to repair even a temporary condition as it is written in: the top part of the next (4th) column towards the right from the left-hand corner which states quite clearly: "G" Any penetrations or damage from temporary welded attachments within the plastic Hinging Zones shall be repaired as required by the Engineer OF Record and shall comply with Part III, item 4.

So then where does one find item 4??? Easy!!!! Look for it... This is found in column 2 from the left side of the document, where it is written as such: 4. Base Metal Repairs or Restorations

Any repair or restoration of base metal shall comply with all of the following:
A. Engineer of Record shall review and approve the WPS for repair procedure prior to welding.
B. Ensure that the repair procedures meet the requirements outlined in AWS Section 5.26 and ASTM A6/A6M-02 Section 9.2. 9.3, 9.4, and 9.5.
C. All welding shall be performed using Low-Hydrogen process or with SMAW using Low-Hydrogen electrodes.
D. Provide continuous visual inspection by the Deputy inspector.
E. Provide Non destructive testing upon the completion of the repair work.

So, what does this have to do with you??? If you do anything to damage or temporarily attach something onto any part within the Hanging plastic zones by drilling a hole, or whatever other method you prefer, whether the area is assembled or NOT, you will be in violation of the contract quality standards, and the GC can back-charge you in order to make the necessary repairs to any part of the  plastic hinge zones - PERIOD!!!

In other words, if you choose to do what you want to do, you will be back-charged for not only the necessary repairs to be performed within the plastic hinge zones, but also for having to have the deputy inspector present at the location where the repair is being performed via constant monitoring as well as the costs for performing the required NDT procedures, andany other associated costs such as the extra costs for the Engineer Of Record to review and approve the repair procedure with his/her stamp, and for the costs involved with the welder actually performing the repair(s)!!! :( :( :(

Now, if this doesn't convince you that it is NOT good idea to do what you want to do, then go ahead and do what you want, or you could ask the GC, or even the EOR and see what they have to say about it. Either way, if you do this, YOU WILL LOSE YOUR SHIRT ON THIS JOB!!! It's pretty Straight Forward IMHO!!! :) :) ;)

Respectfully,
Henry