It sounds as though the new pump and T-stat are doing their job. The rad is doing it's job of exchanging heat as the temps do drop. Double check the sending unit for its on/off temp. Once that side of the equation is dialed in, you can work on the timing and AFR to finish the problem. An adjustable fan controller may be the ticket here as well??

Also, the last pic you have of your rad shows a shroud. Is it sealed up tight to the rad, or does it have some way for air to move through and then out at speed??