Welcome to the forum Monk.1) How difficult is it to swap out an EX-L/Touring steering wheel? Cost?
2) Can an auto dimming inside rear view mirror be retrofitted? Cost?
As S2k_Duke said you can get the heated steering wheel but I have never seen a non leather version offered. I think short of using a wrap there is not much you can do about the leather.
As for the Auto Dimming rear view mirror I am in the same boat as you. I did buy one and figured out that Pin 1 & 2 are 12Vdc power. I THINK if memory serves that pin 1 was the positive.
The problem is that I cannot get the old one off. I see videos of people pulling them forward on other vehicles while doing a slight twisting motion. I tried that but the force exerted got me worried that the windscreen might shatter or the glued on block would break off the glass. So I basically gave up and made a post like yours but no one seemed to know how to remove the non dimming versions since NA only gets the dimming type.
I have looked from behind and I see no clip or screw but the Auto dimming model does have a single screw. My feeling is that even if you get it off, the holding block on the glass is not the same so you might have to remove it and glue in the correct one. This is only a guess on my part but I just abandoned the idea of finding out because the removal of the old one was getting too risky.