I have had several e-mails asking about which pin is what on the Nashville 400 reverb I/O (molex) connector. This has also come up several times here on the forum.
Here is the pin layout on the connector. The pin numbers are my own (not Peavey references). The layout is a jpg file so you can copy it and save it for future reference (on I.E. systems just right click on the drawing and you can save it).
I don't know about the Vegas. I don't have one or have a schematic for it. It may be the same since both amps are similar and designed in the same time frame. However, Murphy's Law always takes precedence..