[SMEDEN(=the blacksmith)]

I have heard, but not tried it myself yet, - if you start by removing the rear wheel, it is easy to get to the alternator bolts with a long extension!
One of my friends experienced it at a Honda workshop in Turkey, about 2000 miles from here.

 

[Andy Cote]

I have seen other guys that have done the same trick to the flanged bolt. Once the bolt is broken loose, it will spin quite easily. You can even use a magnetic pickup tool to move it flat by flat.

While I have seen a couple instances where guys have removed the rear wheel, I have also seen where guys have reached in through the battery box with the right combination of flex sockets and extensions.

Guys have also made new bolts for the one that's hardest to reach. Bring the bolt head all the way out to the end of alternator. I intend to change the bolt next time I pull the battery just in case I have to make an emergency changeout on the road some time. Here's a pic although I will go simpler with just a piece of threaded rod, a flange nut and a jam nut.

 

[gumbyredd]

coastn, I had asked what year 1800 you own, but I see riht off it is a 08.