Welcome to the forum.
I would recommend that you get the bike running well (If it doesn't already). Before modding it.
Yup. Get it working right
before you attack it with a hacksaw.
We're not just being grumpy old poops around here when we say that.
Obviously, we don't know what you're planning, or even what your definition of a "bobber" is. But many first-time builders have the mistaken idea that the first thing to do is to start lopping off hunks of the frame, and making other irrevocable changes.
The thing is, this is just plain backwards. It's insane to start drastically re-engineering something when you have no idea what you started with and even less idea of where you're going with it. Please don't approach your project like this -- we've seen it fail
every single time. Many times.
Starting and finishing a chop/bobber/cafe/whatever project is MUCH easier and a LOT more fun when you start with a running and riding bike. As in the original spirit of the whole modification thing, you're making one change at a time to truly make the bike yours. There's something to do every weekend, and you can explore different ways of making the bike yours. And, of course, you can actually go ride the thing sometimes, which is the whole point, isnt' it?
That's how our Grandpas and Dads did it -- every payday, they'd be poring over blurry ads in the back of disreputable hot rod and biker mags (these days we have blurry photos on disreputable web sites), or haunting junkyards, or drilling and filing and welding out in the garage. The dangerous, sloppy crap you see in half hour TV episodes doesn't work in real life, when blood and bone and lives are at stake.
The GSR community is actually very receptive to modifications and customization, even those on the outer fringes of taste. We're not concerned with originality, either -- there are plenty of rough bikes to go around. Even very stock-looking bikes like mine are modified in dozens of ways.
What we do detest around here are doofs who just start lopping parts off with no thought for little things like running, stopping, going around corners, a place to sit, wiring, noise, steering, or lighting. CrackList is already plenty full of thoughtlessly hacked up, abandoned "boober" projects.
Best wishes for your project! Post lots of pictures, and please search and ask if you have any questions.