Trimmed the saddle on Friday night with tape as a marker/cutting guide and a very sharp craft knife. Decided it was a good idea after a spliff, which can usually mean the complete and utter opposite. Fortunately I was ultra slow and careful so it turned out well. Didn't bother with tabs underneath in the end, something Dale had said in a thread about it being 4mm thick leather and consequently very tough, which makes sense.

Will post a pic up later.