This might sound stupid, but being new to goldwings, and well, exhaust stuff in general, does anyone know what adapter a guy would need to convert the 79 GL1000's exhaust to 1 3/4" for an aftermarket muffler? I took the collar from my new mufflers my wife got me for my birthday into O'Reilly's the other day, and looked at their exhaust parts and pieces, and I just can't wrap my head around exactly what size I'd need. I know rol-tech.com has a list of the part numbers for some of the adapters and stuff Oreilly's carries, but I'm just not sure what ID/OD the exhaust headers are. Any help would be much appreciated, and my apologies for the stupid question!