Hi Jack,
thanks for the image, I think bigted has already established the absolute 'bitsa'-ness of my mower, in fact it's so bad it's good!
I note your scanned image has some print-through from the back side of the sheet. Most untidy of you

but I could make out an interesting bit or two, not least "460"...so I did a bit of image playing. White for black replacement, brightness/contrast/levels and finally an image flip horizontally gives the following. Apologies my skills aren't the best, you'll have to ignore the black-outlined white 'shadow' which is what I tried to hide and concentrate on the black.
Note I think it is slightly confused by a further, but fainter, image from the page behind which again has "460" (reversed) at the top.
Might be worth a couple more scans or page checks, the electric base design might be there?
Cheers,