Mystery vibration at 25 mph can't be diagnosed. It's not the front end!

Ha! Now they are on-board. Finally, the owner was asking all the right questions. Ignition! That was a crazy direction they took. The engine purrs. I collected the keys and said, "see ya." I've had it in storage so long, I never bothered to look at the leaf springs. Yes the previous owner put six leaf springs on it. It should be 5 leafs. That will drop it to the proper rake. I had 3 people stop me and ask all about it when I was at gas station and Wal-Mart. Now I can take it real slow because of my physical condition and look everything over. It's my call now.