89 k bigger rear wheel

[pastyeater]

hi i would like to put a 6" wheel rim on my 89 k  slingshot.I've got a standard swing arm and at the moment, a 5.5 "wheel off a later slingshot with a 180 tyre.fancied the look of a wider wheel but didnt know if possible with standard swing arm .if so wheel off what bike/model/year etc would be easiest to fit .i would like to keep the 3 spoke slanted style of wheel if pos to match the front.any help or advice greatly appreciated thanks