A question about a 6G72 swap

I have an '87 4x4 Power Ram with the G54B and KM145 transmission. Will the 6G72 engine fit without any major modifications? My main concern being the transmission. I have pulled the engine out due to a loss in compression, I'm pretty sure the head's cracked, so I want to see if this is an option before I go get the engine rebuilt. I've seen that the 90+ MM and Montero's come with it. I want to add more power to my truck if possible and of course fuel injection would be nice too :grin::thumbup:
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