Class M Swarf Box Question

[LT580ZX]

I recently found that there appears to be two different size swarf box sizes for the early style Class M evident on machines found on the web. The attachment has photos of four different machines. The first two are what I believe are the original height and shape for the swarf box. Note that there is an appreciable gap between the bottom of the carriage and the top of the swarf box and that the top of the box is horizontal across. The lower two have little distance between the carriage and the box and the top of the box parallels the shape of the carriage. The lower two photos are similar to the reproduction I had made. However, when you try and install the on/off key it conflicts with the taller swarf boxes. One of the members measured their swarf box and it measured 5 ½" to the top which provides the proper clearance. So my question is whether there were two sizes used on the early Class M, one with the on/off key for transcription and one when that option wasn't used. This question doesn't apply to the later version that had the swarf box situated above the drawer. Thanks.

BTW, this is the first time I have tried to attach anything and hopefully there is a word document with four images. If not, this probably doesn't make sense.

[Curt A]

It's better to upload the pictures directly, than in a Word doc...

[LT580ZX]

Thank You

But, note the top two photos are now the ones that are the taller swarf box and bottom two photos the ones I believe are the correct height for the on/off transcription key version. So the photos are reversed from the descripion.