Modified front mount
This modification limits mount movement to about 1/2", as opposed to 1" for a stock mount. A short length of air conditioning hose (it's very stiff and very tough) is bolted to the limit-stop tab. When the mount extends, the hose is compressed between the stop tab and the restraining bracket. In this picture the hose is contacting the restraining bracket, but when installed in the car the weight of the engine compresses the mount and gives about 1/8" of clearance when the engine is not under significant load. Picture
Modification details:
Cut a length of hose and drill a hole in it
Use a countersunk screw to attach the hose to the stop tab
The rear mount did not compress enough to provide clearance between the AC hose and the limit bracket, so some small amount of engine vibration is transmitted at idle. A better way to do the mod for both mounts would probably be to drill the hole all the way through the hose, use a longer screw and put the screw in from the top of the hose. You could then tighten the nut enough to compress the hose sufficiently to allow clearance. As the hose gets compressed (when the mount extends), the screw would extend through the hole in the limit-tab stop. The only thing you'd need to watch for would be to keep the screw short enough to keep it from contacting the mount when the hose was fully compressed.
