Was curious what options were available for VFD with +/- 10v so did a Google, seems quite a few, the GS3 variant from Automation Direct is one, also saw the Delta VFD's seem to have that capability. There were quite a  few others as well.

Hood

Nice conversion! Just wondering, looking at the pics of your control cabinet, what servo drives did you go with? The ones in my mc 500 are huge. Getting ready to convert so trying to find as much info as possible.

Thanks! I ended up using the stock servo drives. I think they're CPCR MR052-nb made by yaskawa. Its a pretty cost effective way to go about a retrofit. Servo drives are quite pricy and the available selection of analog drives is pretty slim. What year is your MC500?