Optima's side posts are not up to the amperes a winch can draw, they mention that on their website. The internal connection that goes to the side post is not up to carrying the >400 amp load a winch can draw. In fact, Optima states that connecting a winch to their batteries will void the warranty.
When I was running an Optima battery, before their quality sank into the toilet, I made a pair of battery-gauge jumper cables so I could use the side posts. The jumpers connected between the side & top posts which carried the winch load up to the top posts. That minimized the load the internal connection had to carry.
I don't have any pics of when I did that for either of my two Yellow Tops but I have one of when I did it for the aux top posts when I ran Optima's Blue Top which is same internally as the Yellow Top. So instead of the two jumpers going to aux posts on top as show, they just went to the side posts in the Yellow Top's case.
My use of photos showing my long-gone Optima Blue Top & of the Optima Red Top photo found on the web in no way endorses Optima. I personally wouldnt' run an Optima battery now if they gave one to me for free.
BlakeDuke123, I don't have a photo of how my winch connects to my current Diehard Platinum battery but I found this pic of a good way to connect the winch leads to the factory connectors. Under the bolts that hold the clamps to the battery.
The photo on the left is of my former Blue Top, the photo on the right is from the web.