I was considering doing that myself as everything is in the way! But I did get the bush in yesterday after all. (Being a Billy No Mates I did manage it on my own.)
I had got both the bolts in and had torqued up the bottom bolt, I could not then get the bush onto the top bolt as it was not central. I then noticed that there was a small gap between the top hole of the R&G block and the frame so loosened the bottom bolt and whacked the block with a mallet to pull in the top, offered up the bush onto the end of the bolt and using an old 300mm+ M8 or 10 engine bolt I had in the bottom of my toolbox (dunno what bike that came off!) and the mallet I was able to tap the bush about halfway into its recess this was then enough to get the washer and nut onto the thread and I was able to sink the bush fully home by doing it up.
The old engine bolt was able to pass by the hoses, exhaust, brackets and oil filter to get a decent contact with the bush.
cheers Derek