Motor mount brackets which side?

On the 66 K-member, you can't use the spool mounts, so you have to use your original 273 style mounts. As you can see from the pic, the block mounting ears are not as wide as the older engine mounts, so you need to use a spacer or washers to fill in the approximately 1/4" difference. On the 360 in the photo, I used washers for the past 16 years, but this time I'm going to weld a piece of metal to the engine bracket itself, then drill the bolt hole through. I'll have a look at my engine mounts tonight and see what the difference is between the two sides, since I can't remember right now. Old Timers Disease. :)