>As a result, I am wondering if I can use a standard PC
>monitor to view the output of the builtin framebuffer.
>I recall seeing some notes on how to get a monochrome
>PC monitor to do this, but nothing on colour monitors.

You can replace a colour DEC monitor 
with almost any modern multisynch
monitor that can accept sync-on-green
(and has the appropriate BNC inputs).

I have used an Iiyama 17" (Vision Master Pro??)
that works quite well. I'm currently using a 
PCXAV-WZ in the office with a VS4K.

As for monochrome, it *might* work if you just
plug the B&W signal straight into the
green BNC connector.

Antonio