does it take a proprietary removal tool
The Parks FR-7 removal tool (that I purchased for the Falcon) fits nicely!
Although it is stated to be slightly larger than the FR-1, (The shape of the FR-7 looks similar to the FR-1 (for Shimano® , Sun Race® , Sachs® and similar freewheels) it works fine on the IRD.
http://www.parktool.com/product/freewheel-remover-fr-7