Transplanting Hibiscus ?

Hello to all,

Have 8 hibiscus. Four are tall growers w lg red flowers, the other 4 are more bush-like a same color flowers but smaller. On the right side, the taller growing H are against back fence, and shorter bushier ones are in front, as they should be. On the rt side however, the taller ones are planted in the front and the shorter ones in the back [which are getting dwafted by less sunlight].

In West Houston, we had no real freezes, and H grew all year long and are still blooming and have been since landscaper planted them in May 2015. In order to transplant them, I wanted to get anyone's real-life experience on a good transfer, as well as how much I should cut them back? They are 6ft tall & 3.5ft tall, [tall ones/bushy ones] on rt side. The left side taller ones are 6ft+ and smaller ones 2-3ft tall. Soil is a crappy gumbo clay, but I amended it last yr w granulated molasses & c-seed meal: great microbial action and TONS OF EARTHWORMS, and H fertilizer too.

Thank you for your help and pls let me know if you have any questions. I want to transplant while it's still not real hot, and we are expecting 3-5" of rain this week.

Regards, tstex