Skipper,
I know you have the plug in Hobie Trax which work fine till you have a boatload of gear you wish not to unload before getting to your vehicle.
I have them too and when tilted kayak to put them in all my gear lay strewn on the ground. Plug in wheels are great for an unloaded kayak but not a loaded one being solo without assistance to lift it up onto them.
though you have purchased the plug in wheels you may wish to look into a non-plug-in cart like the Kayak Cart Mini also by Wheeleez. It has a kickstand and you would just lift the stern up and onto the cart and strap her down. the Mini supports 99lbs but there are some other carts even stronger.
The Mini stores easily in a hatch.
a link with photos:
http://www.kayakfishinggear.com/index.a ... ProdID=157
Other options which would take some ingenuity, is a kickstand attached to the the Hobie Trax to keep it upright as you lift and swing kayak onto it or a portable PVC support rack (that can be disassembled & stored) to hold up the stern high enough while you get the wheels in.
Here is an idea for a kickstand (probably need two for best support)