The SMPS250 module was too high to fit into the 44mm 1RU case. First I had to cut 5mm off the heatsink then I had to change the 400v 320uF main cap, luckily, I managed to find one of the same value but 35mm high. I also had to change the 2 caps on the secondary side but had to lower the value a bit. They were 6800uF 35v, replaced with 4700uF 35v.