Don't worry about traveling thru IL. There's a lot of BS on the internet repeated by people who don't have a clue about IL law. IL firearm laws are not as onerous as some of these ill-informed internet firearm 'experts' portray.
As long as you have a valid CCW from your home state you can have a loaded firearm in your vehicle while traveling thru IL.
Here's IL's statute:
430 ILCS 66/40
(e) Nothing in this Act shall prohibit a non-resident from transporting a concealed firearm within his or her vehicle in Illinois, if the concealed firearm remains within his or her vehicle and the non-resident:
(1) is not prohibited from owning or possessing a firearm under federal law;
(2) is eligible to carry a firearm in public under the laws of his or her state or territory of residence, as evidenced by the possession of a concealed carry license or permit issued by his or her state of residence, if applicable; and
(3) is not in possession of a license under this Act.
If the non-resident leaves his or her vehicle unattended, he or she shall store the firearm within a locked vehicle or locked container within the vehicle in accordance with subsection (b) of Section 65 of this Act.
