Hello again Josh
Sorry to hear you have been having trouble posting.
I wonder whether our experts on the Armed Forces board might be able to offer some advice?
I suggest you post a query there about the military matters eg who was based in Chatham in 1840/1841 and whether grooms in cavalry regiments were soldiers. If you make a cross reference to this thread they will be able to see what has been said so far.
I do hope they can help you.
Barbara