Where the interior is concerned, the steering wheel is the focal point. Because it's one of the first things you see while driving, it's in constant view. With that being the case, an ugly or cracked wheel is nothing but an ocular annoyance when you're driving your Mustang. At each revolution, you get a good view of that bothersome crack or gapping chunk that was the result of the plastic shrinking over the years.
What to do? In this arena, there are a couple alternatives. One is to redo the wheel yourself, using a wheel resto kit such as the one from POR-15. The other is to send the wheel off to one of many parts houses for a rebuild. If you're lucky enough to have a '65-'69 Mustang with the standard wheel, you also can buy a reproduction. All three options have pros and cons. Obviously, if you try to do it yourself and fail, you will still have to send the wheel off and pay for the work. If you send the wheel off, you will be out some bucks, but the job will be correctly performed by pros who know the job because they do it every day. As for the third choice, if you have a Rim-Blow or Deluxe wheel, then you have only the first two choices.
The wheel we are planning on restoring is the Rim-Blow from our Project '70 Mach 1. The wheel on this car is actually missing. Luckily, I dug around in the "I-might-need-that-someday" pile and snagged the original Ginger Rim-Blow from our '72 Lazarus Project. After some POR-15 putty, black and brown paint, new center pad, and Rim-Blow switch from Perogie Enterprises, the wheel will be ready to install after we locate the correct column.