Old, I think you have it backwaords... Moly faced rings must have a very smooth surface finish to break in properly. But when they have that, and it's clean, they seat within minutes of the first fireup. However, I find it's not real common for shops to give the right extra smooth finish. The end result is, the moly is scrubbed off the rings, and they act like std iron rings that take 500-1000 miles to seat. The trick is to load it like CP said. If it doesnt go away, pay careful attention to the carburetor. If it's rich, it may be "washing out" the rings. Where excess fuel removes the oil, and the rings dont seal well. A leakdown test would tell you if the rings have or have not fully seated. I had to re-ring a 383 last year that had gotten 300 miles in 4 years since it was rebuilt. The rings never fully seated because of cold starts and "just warming it up in the garage" on the part of the owner.