Denny,
Last but not least, here is a link to a relevant youtube video demonstrating some repair work to and B500 in operation:
hxxps://www.youtube.com/watch?v=cXxFGDJ4_CE
(replace "xx" with "tt" after you copy and paste the above link to your web browser)
Also of note is there seems to still be some random parts/tooling availability (most found on eBay) that could be useful.
Hope some of this helpful in your project and would love to see how it turns out.