That's right, lowering the full size spare tire provided the necessary room for routing the harness with ease. It might be possible with the spare stowed, particularly if you can work under the vehicle while it's raised in a workshop hoist above you. Doing the install on the ground may limit the angles your hands and elbows can bend when routing it along the rear cross member. Let us know if you're successful with the spare tire stowed, and thanks for asking!
If that’s a full size spare, did you take it down before installing harness?
That's right, lowering the full size spare tire provided the necessary room for routing the harness with ease. It might be possible with the spare stowed, particularly if you can work under the vehicle while it's raised in a workshop hoist above you. Doing the install on the ground may limit the angles your hands and elbows can bend when routing it along the rear cross member. Let us know if you're successful with the spare tire stowed, and thanks for asking!