This is all you need, really. If you also have a lvl 50 version of the Heartbreaker you’re perfectly set. The Bee isn’t needed and 400 stacks is complete overkill, but overkill is nice of course 
I’d move one point to Buck Up since it’s pretty useful in this fight.
If you lack either of those weapons, a good Hyperion shotgun in fire element will get the job done, but you might want to go with transfusion grenades (which are unreliable) or farm up a Harold. Firing the Harold and quickly swapping to a Rubi - not mention a Grog - will heal you to full.
An excellent alternative shotgun is the Blockhead, although it can be painfully slow to farm.
Jill of All Trades COM (for the Hail), Prodigy COM, Anarchist COM, all will work well.
The only trouble is positioning, which you’ll get the hang of. The conventional wisdom is to keep your back towards the exit and vendors, but if you get downed here by one of his cheap double-swipes you might be in real trouble. If he throws you off the cliff you generally keep your stacks, so it’s a matter of choosing your poison.
If you do lose your stacks you can beat him anyway, it just takes a bit longer. Rational Anarchist and Typecast Iconoclast should get you some fresh stacks in no time and you really don’t need many at lvl 50.
When you release DT, Terra can sometimes spam his ground pound repeatedly. This makes middle range deadly, but can give you a good opportunity to charge down the guns and get some free damage in from close range, since his swipes will usually go far above your head.
If/when you get the opportunity, releasing DT when Terra has sent you flying above the map is a good option, since he’ll usually stay at that elevation for a while and draw ranged attacks far from you.
While it’s tempting to repeat my general motto for Gaige (“When in doubt, facetank”) this only holds true if you have a Hail, Heartbreaker, Kitten or similar, given Terra’s knack for hitting you hard and then going underground.
Otherwise, use available cover and build your stacks. Throw transfusions with abandon, killing his tentacles will restock you.
Like any raid Terra will seem daunting at first, but you’ll soon be surprised at how easy it is - and itching for a rematch in UVHM. Have fun.