The C14 is a big bike, I'm not sure I'd be comfortable getting it in or out of a pickup bed. Also if you rest the rear on the tailgate you might buckle it and I'm sure you'd be really sad. Don't tow it with the rear wheel on the ground! The transmission will always move when the rear wheel is moving but the oil circulation is from the engine-driven oil pump. You can cause damage due to lack of lubrication if you tow like this.
If you can't ride it home, get a trailer that will get both wheels off the ground.
Do NOT strap it down using the handlebars, they are aluminum and will snap! Use soft-ties on the lower triple-tree clamp taking care to avoid pinching any brake lines. Cinch it down pretty tight. Then I like to just use one strap across the final drive housing to keep the back from bouncing around.
Also be sure to closely check EVERYTHING for damage. The first thing that comes to my mind with a damaged tank is that they dropped it. I can't believe that the tank would be the only thing damaged. Here is a trick that I use, act like you're cleaning the bike with your hand, look and feel for any damaged body panels. I'm guess you paid for a "new" bike, not a wrecked one. If it's not right either make them fix it right or get some financial consideration.
Note that the underside of the tank has panels covering it. These are NOT a part of the new fuel tank but are separate items. It's impossible to peel these off and get them to stick again, so they either glued them on or just left them off and figured you'd miss it.