Have you used EC solo before? Alpha-y is usually better for this stack compared to using yohimbine-hcl, but definitely start with a low dose if you decide to stack these. I find that EC + y-hcl gets me very anxious and jittery. Alpha-y seems to give me less sides and I can handle it better.
Also, be mindful of you workout intensity and heart rate if you decide to run this stack. It's a lot of stimulants, so be sure you aren't shooting your heart rate through the roof. I've always found that EC + 1 cap of TA2-Max (3mg alpha-y) works great as stack for fatloss.