Fitting a narrower tank. No. Too much trouble. Lots of fabricating. Don't have all the tools.
Widen the bars! I have tools to do this. I have mate, Big Dog, who has TIG welder. One very large bolt was bought to be turned into a slug. 4" was cut out of another set of bars. Holes drilled.
Rode to Big Dogs place. He welded the extension in. Grinder over welds. I get home. File and emery paper to smooth out the grinding. Coat of Satin Black.