t-real1

I put a 1996 LT1 with aluminum heads and 49,000 miles from a 1996 Z28 into a 1996 Buick Roadmaster Collectors Edition recently. Perfect fit. A week later while doing 40mph I stepped on it and shot to 80mph on a nice stretch. As soon as I got to 80mph the car seemed to stumble and slowed on its own then picked back up.I then slowed it down and it went a mile more with normal driving (35mph) then shut completely off and rolled to a stop. I tried to restart and it turned over but I could hear a clicking/jangle type sound coming from the engine during my attempt to crank it back up. Checked fuel pressure. GOOD. Checked for spark and found none. Replaced opti and still no spark and still getting the noises during cranking. I also discovered that I did not ground the engine during the swap. I was told that it may be my ICM and coil? I had them checked and it was no spark/bad. So now I'm waiting on one from ebay to see if it will solve my problem. But I don't know what's going on? Is it the oil pump drive gear causing both the noise and the lack of spark, as I'm guessing? Or the ICM and Coil as I was told? I cant get past the motor in order to finish the rest of the car.... Any help would be appreciated. Thanks