Guns: 
Bod is overall my favorite, it counts as ALL weapons so it will proc 
Blood Shot via 
Undead Eye because it shoots many projectiles and counts as a sniper rifle. I recommend having one roll with the sniper mode underbarrel, and ideally a CoV magazine. It can roll all sorts of different stuff and it's extremely strong by default so I wouldn't stress too much about getting a perfect roll, and I would encourage trying different variations out!
Finnity XXX-L is another strong option for bossing however you'll likely need a particular CoV enhancement to use with it, granting you 100% crit chance while the mag is overheating. I would not recommend it for mobbing, it feels bad and is inferior to the Bod in pretty much every conceivable way.
Complex Root with atlas tracking darts is extremely good for bossing as well, but can be inconsistent at times and doesn't feel great for mobbing
You can probably use any sniper for mobbing if you prefer, but it's unlikely it will be as strong as Bod
Shield: 
Timekeeper's New Shield is BiS because it gives you flat HP to help scale your Blood Shot
Repkits: I like using 
War Paint with enrage for extra damage. Lifesteal rolls on your repkit doesn't apply to 
Blood Is Power unfortunately.
Class mod: Undead Eye is mandatory, try to aim for +5 into Blood Shot, the other 2 rolls aren't as significant. It will always roll with sniper damage, for the top portion damage reduction, movement speed, health, and gun damage are all good options.
Enhancements: Prioritize getting additional gun damage, and keep in mind the Bod counts as all weapon types! Gun damage on enhancements are multiplicative, so if you get gun damage + sniper damage, that will boost your damage by over 50% which is pretty insane. Fire rate and mag size help out too! If your Bod is a CoV you want to get a CoV enhancement ideally but it's hard to get a well rolled one. Ripper/Torgue enhancements can be good as well if your Bod rolled with a part from them, but again just prioritize damage.
Item Locations:
Bod = Axemaul, Auger Mine, Carcadia District
Finnity XXX-L = Battle Wagon, Ripper Drill Site, Stoneblood Forest
Complex Root = Mimicron, Order Bunker, Idolator's Noose
Timekeeper's New Shield = Timekeeper, The Timekeeper's Order, Terminus District
Undead Eye = Vile Lictor, Umbral Foundry, Windspear
War Paint = Saddleback, Ripper Drill Site, Cuspid Climb
Vex
Incarnate
Bloodletter builds because the damage happens instantly. 
