I was given some good advice on alternative engine mounts. These are GM LS1 engine mounts. Pretty much the same but M12 thread as opposed to the ZX M10 thread, the thread studs are longer also so need to be cut down. Bought them from Veals for $65ea. Quote for 300 ZX mounts, $250ea. Small amount of work for a big saving.
Then you find out they still fail. The left mount on the ls engined commodores fails just like the stock tt one. Except a lot earlier. They do not have the torque hook down the side that limits the stretch of the rubber like the tt one does. Stock is still by far the best solution.... Expect to be replacing then somewhat early. I had to replace one side on Scotts SS ute at 50000klms Look on ebay. $64 each plus $20 post, auction 141174951914 At least it's the right part.