Thanks for the comments guys. Skip, I know what you mean about the tire seams.
First, an interesting story. This kit, (again, it is an original), came with the wrong rear tires. I was asking my model buddies Gary Kulchock and Chip Wamsley about how to get the tires to fit on the rims. They pointed out that they remembered from way back that some of Tamiya's 1:12 kits had the wrong tires. We checked the ones I had vs. some other 1:12 kits and sure enough, mine were too small. Gary was kind enough to give me a pair of rear tires for this build.
Back to the seams. I was able to hand-sand the rear tires to what I feel was an acceptable level. The front tires had such a huge seam and a bit of a step that I thought by the time I sanded them down I would also have wiped out the wear marks, (those three hash marks across the face of the tire).
One other thing about those seams. I have a picture of the 1:1 car with brand new tires and there is a visible seam down the middle. Not a drawn on line but a seam. I lost a gold medal in an IPMS contest, (not this car and I got a silver instead), and when I talked to one of the judges about what I could have done better or what I did wrong, he pointed out the seam in the tires. Once again I had a photo of the real car with what sure looked like a seam on a new set tires.
I readily admit that 99.99% of any pictures you would come across of any race tire from any era would not have a seam. But 99.99% is not 100% . Anyone else care to weigh in?