When Carol is helping Wayne from the bar to the car, the outline of his body microphone and wire is clearly visible on his left chest under his tight shirt.
While the bank sign says "Toaster" and Newman says "Toaster/Oven. It is actually a Rival Toaster Oven/Broiler according to the box behind Farwell in the bank and when Carol brings the box into the car; however, at that point Newman now refers to it ad a "Toaster".
While the talk is about toaster ovens, the bank offers toasters only - the billboards clearly show a toaster and the description is 'toaster', not 'toaster oven'.
In the greenhouse scene Carol's necklace clasp is low, then in the close up shots, the clasp is higher up. Also throughout the movie she never wears her wedding ring and at the end she wants it cut off.
A cat scan would have revealed that Paul Newman's character did NOT have a stroke.