Would it be better to buy a single or to small twins for 75 or 90 horse DDP injectors 3k govener springs ground plate mod afc and everything slid foward and 5inch turbo back with 4inch down pipe.

If twins would be the way to go then what size should i get. Or can i use my stock turbo and another turbo. And how hard is it to make or find the pluming to do all of this.
I was thinking with a single to get like a 62/71/14 or a 62/65/14. I dont do much towing but i do tow some. thanks for any help