Actually I'll change the original goal of this topic and include what I'm working on.
I don't have a lot of money so I bought an ASI585MC non pro, which means it's not cooled. I want to use it to photograph DSO.
I'll test stock, measure the temperature and include dark frames with various exposure times.
I'll then compare it using a home made cooler using a peltier and a computer CPU fan and heatsink.
I just opened it up and there seems to be a way to include a copper plate between the motherboard and the sensor board but it will depends on the results on using the peltier directly on the camera case, without any internal changes.
I'll include all the STL files and a list of the components I'm using in case someone wants to replicate it.
For now I'm testing the case to make sure it all fit together. I'll buy a 10mm thick insulation tape tomorrow. I already have the peltier and temperature controller.
It looks weird for now because that's just the parts that will be 3D printed. I'll include photos once it's done printing tomorrow.