Not sure if you have the Kaypro technical manual (available http://bitsavers.trailing-edge.com/pdf/kaypro/
The machine is the spec described as a Kaypro 4 in section 3.3. of that document.
I haven't powered it up yet... removed the power supply and will sort out the capacitors first. Saves smelling out the workshop and gives me time to make some disks. The machine didn't come with any.
>The TRS80 Model 4 had a BASIC in ROM which maybe lead to more board complexity? I've never had a good look at my Model 4 board actually.
I shouldn't imagine that Basic in ROM would have made that much difference... an extra ROM chip and some address and chip enable decoding. I could imagine that the Model III compatibility might have contributed though. Also on my Model 4's the main board is probably 30% larger than the Kaypro with the Floppy Controller and Serial Interface on separate boards.