First of all, about oil.. Here is what simplyconnected had to say about oil and zinc in a recent post.
"Everyone is an authority on oil. I am not, but I know our flat-tappet engines really depend on zinc as a 'last resort' for engine wear due to lack of lubrication.
Just about any engine oil with '40' (like 10W-40) in the numbers has 1,000ppm of ZDDP (Zinc Dialkyl-Dithio-Phosphate). I use Rotella-T 15W-40 for several reasons. ZDDP content, lubricity, low ash, detergent cleanliness, cost, it beats every API rating, etc.
This oil is NOT recommended for cars with catalytic converters because the platinum substrate can't deal with phosphorus and zinc.
BTW, 'low ash' is a result from burned oil. Remember, piston rings rotate by design. Randomly, the end gaps align causing a blow torch affect down the cylinder which burns oil. Low ash will inhibit sludge which clogs your pickup screen. - Dave"
So, if was me, I would go with Rotella-T 15W-40 because it is my understanding that only the -40 weight oils still have that much ZDDP zinc in them. The other weights have had the amount of zinc reduced greatly.
Now for steering wheels. Original or replacement steering wheels are hard to come by. However, Jed Zimmerman, here on our Forum, restores your old steering wheel to like new condition. He did mine and others, and they look like brand new steering wheels. If he has any spares, he can mail you one, and you send him yours after you get his. That way, your car will not be out of commission very long while he restores your steering wheel. If he has no spares, then you will have to send him yours and wait for him to get it back to you. You will find his listing in the Advertisement Forum below. He also makes all the seat foams for our 1958-1966 Tbirds. Most Tbird parts houses buy their foam stock from him!