[Chad Hauris]

I wouldn't say it was a mess, it was a pretty decent conversion, although of course the original chassis would be better. Repairs would be just like restoring that chassis in a different cabinet. Looks like it was fairly neatly done.
It may be that the original chassis was discarded years before the retrofit was done and the newer chassis was installed to create a complete functioning unit, and I don't think there is anything wrong with that situation as I have a similar type early 1930's cabinet with no chassis that will need something retrofitted into it to operate.