Yes!
Apologies for my mistake and thereby adding confusion.
The model is indeed slide-valve and the inlet is at the top with the exhaust through the frames as Duncan writes. When you get the drawings this will be clearer.
There is a four page article about a similar 5" gauge model 'Hall' in Model Engineer magazine, Vol.80, No.1987, June 8th 1939, pages667-670, which although unattributed appears to have been written by Greenly.
I have uploaded Greenly's dimensioned General Arrangement drawing to my album. You may be able to compare principal dimensions with what you have?
Thanks to Duncan for the prompt correction.
Edited By Weary on 27/03/2022 19:56:43