Adding a Shurflo pump to a Windrush

Hi, I'm hoping for some help! I have a 2011 Windrush and although the submersible pump is still functioning, the pressure is pretty poor. I would ideally like to add a Shurflo pump, like we had in our previous Nuevo to the Windrush, preferably inside the van but I can't find where the pipes come up though the floor. I'm concerned that when looking at the tank under the van, it looks like there are two outlets from the tank, possibly one to cold and one to hot? Does this mean that the pipework splits inside the tank rather than inside the van? If this is the case, would adding the Shurflo be impossible?

Hope that makes sense! There don't seem to be many Windrushes around so I hope someone might have some advice
Thank you.