You cannot really adjust for left-right alignment. You place the pins/bolts in the rear motor mounts and you then cannot adjust left-right. The only way to get left/right alignment is to compress the rubber in the rear mounts or the slop between the bolt and the rear motor mount hole, of which both I don't think is significant.
You can also rotate the engine along the axis of the driveshaft by only turning one side. I've read the best way to do this is to lift the engine up slightly by the center hook which you don't have. I also was not able to do this, so I measured the height of the rear motor mounts sticking up. Kind of hard to explain, but the 1/2" spacer, washer and bolt head ride on the inside of the rubber motor mount. The outside is fixed to the motor bell housing which sits in a lip and cannot go up. So if one side of the spacer is sticking up high, it means there is more load on that side pushing the inside rubber, and bolt head up. I adjusted front left/right so this gap was even, theoritically having even load on the rear engine mounts. I figured this out when one rear mount was originally not even touching (after rebuild) and the engine was basically sitting on 3 points. From there, I went up/down together to get alignment correct. If witness marks are on top, raise the front of the engine. If witness marks on the bottom, lower the front of the engine.
They also sell spacers in the rare case that the alignment does not line up. Seems like it may be older models that need this, but I'm not sure on the details.