Calvin, two points here...WHY is the rear axle bolt hitting the right side muffler, when 99.999314159 percent of the other Goldwing 1500's don't have this problem ?
Secondly, rather than cut off the threaded end of the bolt...why not space the bolt out to the left, by placing one or two thick washers under the head of the bolt, on the left side of the bike, before sliding the bolt through the rear differential ???
Oh ya. I think I'll ask the Goldwing guys (or anyone here with a 1500) to air up their rear shock and see if the bolt hit's the muffler?
I feel SO bad for Wilton, thee Dog. 
Calvin, I previously owned a 1994, and a 2000 Goldwing 1500, and on both of them I removed the original rear shocks, and installed Progressive Suspension coil springs shocks, and neither of those bikes ever had the rear axle bolt hit a muffler, on either side. Both bikes were ridden HARD.
And I just polled all previous owners of Goldwing 1500's, and they all agree....everyone of them....we all feel SO bad for Wilton thee Dog.
In reality, I would bet that at least 75% of all Goldwing 1500's had the rear suspension replaced, because that was the biggest flaw on those bikes. There was an air shock on one side, and a coil spring shock on the other side, so in high speed sweepers the bike would wallow.
Two Million Mile Rider...All 7 Continents
Exploring the World in Comfort
Wow. I forgot about that. I had a 1988 & a 1997 1500 and had forgotten about that 1side had the adjustable air & the other coil over.
Hmmmm. I just watched a bunch of Goldwing videos trying to get a look at that bolt. They all look like it's up there where mine is,,, from what I could tell.
One video in particular showed a guy installed these same 412 shocks. He set them on max load. He said it raised his bike about 1.5''. He made no mention of the bolt hitting.
So I don't know what the heck I've got going on. It didn't hit before I swapped final drives. The one I installed is supposed to be out of a 93. I don't seem to be having any other issues.
Calvin, Caretaker of Wilton thee Dog, aka...Sidecar Willie, before you installed this used Rear Diff, did you make certain that it was the exact same outside casing as you old one? Placed them side by side, and carefully compared them,,,every nook and cranny ?
I would love to see a picture, or two, of the LEFT side of this replacement rear diff, with the axle bolt installed.
Two Million Mile Rider...All 7 Continents
Exploring the World in Comfort
Sounds like there is something causing offset. Not being a GW veteran, I can't offer anything specific, but there has to be something causing it to be shifted to one side.
Illegitemi non carborundum est!
I know I'm not there to see it, but, the mufflers can pivot inward and outward where they meet the collector box, if I'm remembering this right why not just bend the tab on the muffler where it mounts to the saddlebag bracket a little and twist it out a little to clear the bolt all together
Calvin, Caretaker of Wilton thee Dog, aka...Sidecar Willie, before you installed this used Rear Diff, did you make certain that it was the exact same outside casing as you old one? Placed them side by side, and carefully compared them,,,every nook and cranny ?
I would love to see a picture, or two, of the LEFT side of this replacement rear diff, with the axle bolt installed.
I compared both final drives before I installed. They looked the same. I just looked at them again, all though I can only see the right side. They look the same. I compared all the parts using partzilla. They all interchange from 93-96.
There's no moving the swing arm over. So that's where it has to go. The new final drive bolted up just fine.
Sure seems like if I had a major problem I would be able to tell with the 300 miles I put on it?
Let's see if I can get these in the right order. This is the space between the washer and frame with REPLACEMENT FINAL DRIVE.
Here is the ORIGINAL FINAL DRIVE spacing before removal.
