Ok guys I need some Guidance here. I have wear on a thrust bearing that is being caused by some kind of alignment issue.
Each time I put the engine in, the alignment tool slides right in. What else could cause this.

The pics and thread I started is

Does this THRUST BEARING look ok to you?

I read your other thread as it was unfolding. My opinion is if the alignment tool slides in and out smoothly, then it cant be out of alignment. Maybe your problem is the engine or gimbal moving around under load?? How are the mounts and condition of the gimbal?? How about a bent input shaft on the drive? I had a problem once where the alignment tool went in but the drive wouldnt. I changed the input shaft on the drive, problem solved.

I also dont like the Merc alignment tool. It just slides into the coupler. I prefer cutting up an old input shaft. that way it actually slides into the splines. It will tell you if the coupler is twisted. Maybe when you bolt on the drive, it is pushing up against the coupler forcing it forward?