Disconnect and remove ALL the ancillaries from the engine.....................double check.................that everything is off and out of the way 
What you should now be left with is an engine with 4 bolts holding it in place............given that yours is an H you may have already removed the front engine bolts when taking the rad off..............dont matter if you have
Slacken the 4 engine bolts
remove the two front engine bolts if they are still there..............the engine is now hanging on the two rear bolts.
Now you need a friend or some means or supporting the engine..................(I use a home made thing that I made from an old carjack)
Remove the lower rear engine mounting ...............now with your friend or supporting deivce hold the weight of the engine so that the weight is lifted off the final bolt and remove it....................the engine may still be stuck or jammed inplace but because you double checked everything was removed it should with a bit of wriggling drop out................it can snag on the front engine mounts..................but down and out it should come
Easy really..................I can do it in less than an hour on my own.................and have afresh one back and in and running in another two
If it helps...................ANY ZXR model engine will fit as a replacment.................you might just find that repairing yours is........expensive.
I very much doubt if the restristor either the Kawasaki one or anftermarket 33bhp one was responsible for blowing a hole in the bottom of you engine..sounds to me more like a big end let go..........................bang
Go do a proper introduction......................please.
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