Finding a correctly seamed un-padded vinyl top has been a real challenge. I found that SMS Fabrics (http://www.smsautofabrics.com/
) in Oregon has the correct un-padded material. They made two tops for us. Upon inspection I was very disappointed with the look of the seams. They looked as if a machine pressed them too hard and flattened out or distorted the original vinyl grain.
I wanted to return them for a refund. SMS said they don't refund but they said they would make me a satisfied customer by re-making the tops. I agreed and sent the original two back to them. They have been very difficult to communicate with, by not returning calls. So the latest is that they looked at the two tops I sent back and told me "The seams are perfect. There is nothing wrong with their tops" You know, I expected that reply. I'm calling them tomorrow and will escalate the issue. What makes this all even more disturbing was the price I paid. With shipping, the two tops were $600. This is just about 3 times the price of the tops from Rick's. SMS said they were the only company using the original un-padded material. For that I expected the cost to be higher.
So to answer your question, no I haven't found a correctly seamed top. Not yet! We will not have the 68 RS/SS at the nationals. But, if all goes well we will have a 69 Daytona Yellow Z/28 with a vinyl top.