Tax planning question

[Christopher Sarmiento]

While I wait for my Tax lady to respond to my email I wanted to post my question in the BP forums to see if I'm thinking things through correctly. 

I own a Duplex in Florida that I'm going to sell and it is my primary. I bought it for 410K and I'm currently listing it for 720K, and i was informed that I would be taxed around 50K since I only lived in 1 unit for 3 years. I have a HELOC of around 120K on this duplex, and I owe around 120K on a SFH in Florida too.

All that being said, would it be possible for me to pull 120K out of my HELOC to pay for my SFH before the sale of my Duplex? Since the lender will pay off my debts first, and I won't touch the profits yet, do I get taxed after I pay off all my debts and get the remainder? Or am I taxed for the the capital gains before it pays off my debts, so all this movement isn't necessary? I plan on doing a cash-out refi to get that tax free money back out

I'm not doing a 1031 because I'm moving to Georgia after this sale and have a lot of other moving parts to think about. Would this be possible? Am I approaching this scenario correctly? 

Thanks for the input BP community 

Chris