Rapid distributor gear wear on roller cam 351

[fxbill]

Hi,
I recently purchased a 67 Cobra replica with a 351 Windsor in it...(78 I believe. Since it was a sled... beautiful, but a dog nevertheless, I decided to pep things up a bit. The engine had only a few hundred miles on it so I opted to work with it. I pulled the Twist Wedge heads from my 85 Mustang and purchased an F303 roller cam after being told that I could simply drill and tap the holes for a stock spider lifter retainer and run with that cam. After installing the heads and cam I realized that the lifter bores were lower in the early 351 and the lifters came up too far anything to work...the oil holes in the lifters were exposed on the high side of the lift. I then purchased a set of crane roller lifters and that seemed to do the trick. I re assembled everything, installed a Weiand "stealth" manifold and Holley 750 carb. The thing ran like a rocketship for about 10 miles and then the problem began. The car just stalled the other day and after having to tow it home I discovered that the distributor gear had completely disintegrated! Actually it had worn down, but at an extraordinary rate. I checked with the local speed shop and was told that I needed a steel gear with the roller cam instead of the cast iron gear that came with the early engine. $40 for the new gear and 4 oil changes later to try to clean out the metal from the engine and I was ready to try it again. I cranked up the car and ran it for about 10 minutes, pulled the distributor again and it's already beginning to show signs of wear. Maybe it's just breaking in...haven't driven it long enough to really tell, but I have a bad felling about it.
My question to any of you is...Has anyone gone through a problem like this? Any suggestions would be greatly appreciated.
Thanks,
Bill