Roly, you're an absolute gem for taking the time to look that up. Thank you.
The overall dimensions are correct but the flour bin is removable, not lowering, and the casters don't have the ant-proof ring for borax. There is evidence of a missing fixture on the right hand side which was possibly the sugar bracket you mentioned. There is also a set of nail holes on the right hand side, just underneath the pull out counter, but that could have been from an addition of a towel rack or something.
It looks as if the top panels are glass underneath the paint, but the embossing of the left two are a different pattern, stippled, whereas the right one is frosted. Weird. I can't see any evidence of the panel being taken apart to replace a glass but grandpa was an excellent woodworker so that doesn't mean it wasn't done.
If there was a sugar canister, it may still be at the homestead if it wasn't broken, so I will have a look. Thanks for drawing my attention to it.
There is a label underneath the counter which I can't see unless I take the thing apart that may give a clue...I think I will have to disassemble it soon as I'm curious now

I like your solution to the porcelain top.
Mandy, thanks for the kind words. I think grandma would approve if I get the trailer done first, so it'll stay the way it is for a while...
