Hi Oma
Yes, it's fine to post snippets of a previous post in a reply

I see what you mean about him being rather elusive - there aren't many of them to be found in the English & Welsh records though I see a few Irish references scattered about

Do you know his religion

Unfortunately, the army documents are at Kew, London and I don't think any of what you require is yet available online. I would assume that he was probably discharged to pension as he was in the RA for rather a long time.
The discharges for this time period do not have a complete index, they are sorted by surname (roughly) ie. the first three letters and they original documents are housed in a large box which has to be sorted through to find the correct one. I would expect/hope his discharge document to be in the following box:
Piece details: WO 97/3813
Scho - Scl
1883-1900
Perhaps you could find somebody kind enough to look this out on your behalf otherwise I'm not sure how much it would cost to employ a professional researcher to do this for you. The discharge document is probably the one to start army research from this time period.
Casalguidi