I picked this up while at the dealer for service (it's the 'emergency assistance kit', and there's no instructions as to how you're to mount it w/ the supplied Dstrap-thingie. Pictures to illustrate my solution so far:

I'm not so sure that there is a designated space for mounting that, but I could be wrong.

ideas on where to put it are appreciated; I'm tired of it rolling around, and I'm not sure what I've strapped it to is the best

Hot glue a Velcro strip to it and fasten it to the fender well.

From the accessory install manual (therefore, not very useful):

Care must be taken when installing this accessory to ensure damage does not occur to the vehicle. The installation of this
accessory should follow approved guidelines to ensure a quality installation.
These guidelines can be found in the "Accessory Installation Practices" document.
This document covers such items as:-
• Vehicle Protection (use of covers and blankets, cleaning chemicals, etc.).
• Safety (eye protection, rechecking torque procedure, etc.).
• Vehicle Disassembly/Reassembly (panel removal, part storage, etc.).
• Electrical Component Disassembly/Reassembly (battery disconnection, connector removal, etc.).
Please see your Toyota dealer for a copy of this document.
NOTES: “FAK” denotes First Aid Kit
1. Install First Aid Kit.
(A) Cars / SUVs / VAN: Place the FAK in the
right rear corner of the trunk / cargo area of
the vehicle. (Do not remove FAK from
package). (Fig 1-1)
Whenever possible, “Toyota” name is
visible and upright.

Fig 1-1:

Attached Images

 

Could you elaborate on that a bit? Where's the fender well?

It's where the troll hangs out.

Just shove that thing under the seat.

doesn't fit under the seat, it's too thick. The FAK however fits perfectly under the RR passanger's seat. I'm thinking of cutting through some plastic and making an attachment point for the d clamps...

He's referring to the area behind and to the outside of where the wheel well protrudes into the cargo area. On the drivers side this is also where the access panel is for the jack. Depending on what options your truck has, the passenger side may have cubbie holes that you could store it in (see below). You could also store it in either the glove box or center console box.

Attached Images

 

GrantK, ah, right! Yes, the 'emergency assistance kit' certainly won't fit there. Note that this is the ...



It's much larger than the First aid kit.

The EAK has the same Toyota instructions and picture as the 1st-aid kit:

NOTES: “EAK” denotes Emergency Assistance
Kit
Included strap is for end-user to secure
EAK as applicable.
1. Install Emergency Assistance Kit.
(A) Cars / SUVs / VAN:
(1) Place the EAK in the right rear corner of
the trunk / cargo area of the vehicle.
(Do not remove EAK from package).
(Fig. 1-1)

Where are you finding the instructions for install?

The Misc.zip file linked to via the TIS FSM link in the Modifications sticky thread.

Looks like you may need to buy a bigger truck.

Or.....