That right rubber mount won't last very long with that much stretch. Are these brackets new, or are they old used items that have been repainted? If they are new, I wonder if someone bent them incorrectly. All the big blocks I remember had the brackets on the front side of the block ears, but then again, its been a long time. It also seems to me that the studs on the rubber mounts are off set, can you gain the difference you need by turning or flipping the rubber mounts?

Moving the brackets to the front of the ear will give you the difference you need. I'd probably put a spacer between the bracket and the rear ear, or see if I could open up the bracket to fit better (likely I'd do both). I Believe those brackets are squished together or improperly bent, or the studs in the rubber piece is not oriented correctly. Gene