Todd, is there an access hole under where your back seat pad will be? If not, this might be a very good time to cut one.
Otherwise, there should be a plate on the front of the tunnel big enough to see through with a flashlight. It'll be on the frame head, held in with two bolts.
If you can have someone hold the flashlight for you and guide you through the bushing and to the coupler at the back of the tunnel, you might be better off than trying to do it blind.
When you get it through the bushing and lined up in the back, don't cap up the shifter assembly until after you've attached the coupler. Put the coupler on the shift rod first, put the bolt through and then move coupler into position on the shaft coming out of the transmission.
If you don't put the shifter assembly on first, you can pull the cup down and to the left, making it easier to ratchet the bolt into the coupler on the end of the shift rod; it'll be sticking end-up with the insertion hole aimed at the clouds. When it's on, line up the cup, pack it with grease, tilt it back to the right, center it between the bolt holes on the tunnel and you'll be in business.
Also, if you have a welder close at hand, or if you can get to one, put a couple tack welds on the coupler itself where the O meets the T (photo), to prevent it getting sloppy in the future.
From my recent experience, my shift rod is also a half-inch longer than I want it to be. I have a harder time than I should getting reverse to work. Might want to have a look at that on yours, too, and maybe save yourself some aggrivation.
Mine was cut where the pans were when the Bug was chopped to make the kit. The library has the FiberFab description on how to measure it:
https://www.speedsterowners.com/library/fiberfaba/images/fiberfaba021.jpg
... and, since I've never noticed or commented on them before, your phone dial wheels are BRILLIANT!