I found this bit of information last night from the manufacturers

Note that while the vast majority of Escort Cosworth owners had no trouble installing this mount on their vehicles, there have been a couple owners that mentioned the rear sway bar needs to be adjusted rearward a bit to clear this mount. One owner filed down the lower diff mount bolt head a bit to solve the problem. If you are purchasing this mount to install on an Escort Cosworth, please understand that you may have to adjust your rear sway bar to complete the installation, or clearance the diff mount bolts. Sierra and XR4Ti owners need not concern themselves with this, as the mount fits perfectly in all situations.

Damn yanks