update on exploded intake....finally fixed it!
As I suspected, the fuel pressure regulator went south, flooding the intake with fuel which caused explosion when cranked. I bought a Dorman intake off eBay for $115 and put it on. Pretty easy really, only took about 2 hours. I decided to do a lot of other stuff while i was getting dirty. Replaced FPR of course, and also changed hoses, serp belt, PCV valve. Installed new Delco platinum plugs, MSD coils and 8.5 wires. Big difference in driveability, much smoother. Car runs great! I also finally got around to replacing noisy fuel pump. I ordered a pump from gmpartsdirect.com and they sent the wrong one. Guess I should have checked before taking the car apart. Had to buy one at retail from local dealer.
Anyway, the Dorman intake seems to be very high quality and is obviously more robust than the factory stocker. Documentation even says it is strengthened to withstand backfire.
Now all I gotta do is find a new engine cover. Mine is blown to pieces!
Hopefully good now for another 110K miles.