THG: With these components being so densely fit into the toaster, would you say this is safe for permanent operation? How would you ensure proper air flow inside the toaster?

Dave Goeke: Depending on the processor, a CPU fan may be necessary. The Cyrix 200 seems to work fine with just a heat sink, but I put a fan on it anyway. Drives tend to get warm, and space in a well-designed Toaster RAID is limited. A cooling fan for the enclosure will help. Given the tight fit, the best fans to use are small CPU fans. There are some that tend to run silent. Mount them to blow air up and out the top.

Wiring

Dave Goeke: The inside of the toaster will quickly become cramped and short on space. Some of the ATA and power wires will need to be connected before final assembly, because the interfaces become unreachable once components are installed. My systems both use very short (6 inch) non-standard ATA cables. A lot of things often do not fit quite right at first, and in the normal course of building a Toaster RAID it is common to repeatedly assemble, disassemble, then reassemble significant portions of the system.

THG: I suppose there is no way to get away from playing around with the components until you are happy with the result.

In the course of trying to fit everything in such a cramped space, the systems were assembled, disassembled and reassembled numerous times. All the wiring takes up more room than may be expected.