First off, Congratulations on the acquisition. The drivers should have been in the rear box if it is anything like my 2400. The steppers were mounted with a small board at each axis. This board was to combine the limit switch wiring and stepper wiring into 1 harness. The lamda power supplies are good but only 24V and 5V in mine. The 5v is used for the spindle control board. My 2400 has a Bijur auto oiler on all 3 axis. I have run mine with a G540 and the original steppers quite successfully but would prefer a direct drive. I am in no rush to change it though as the machines travels are too small to put much more effort into, IMO. If the leadscrews and nuts are similar to mine, they are of high quality. My backlash measurements were always .001 or less and generally less than .0003 if my memory serves me right. The quality of machining is top notch and all aspects of the machine are top rate especially considering it is a 1980's or earlier design. I believe there were 2 builds I can think of with that machine here on the zone. Why do you say the ways are nothing special? That frosting is hand scraped. Regarding the interface of the spindle with Mach, I run my spindle manually at the moment but could see 2 ways of solving that issue. First just use a relay thru the G540 or BB board and have it control the on/off of the spindle. Second would be to possibly switch it direct by connecting or disconnecting the ground to the spindle control board. The original set up was like this with a switch that let you select between manual or auto control. I personally have not tried to switch it thru my G540 until I can verify the grounds from the machine and or computer side are not linked. Electronic parts are rare on this machine. A retrofit would be possible if I fried it but no rush just yet.