I'm not sure my mum would approve of my showing my crotch on the internet, but this is what the inside looked like at this point:
Now I stitched together the reamining side seam with my overlocker, threaded the loose ends through the seam with a wool needle, and ta daaaaaaaaaaaaaaaaaaaaaaa:
I finished these about an hour ago, and I'm wearing them now, so I'm not quite ready to give a full evaluation, but first impressions are good. The overall fit looks and feels nice and comfy, but I had a little concern that maybe the elastic at the leg holes may rub against my skin a little. This may be because the overlocking I did to initially attach the elastic and fabric is a little rough, OR because the elastic itself is a little course (some elastics sold for pants making has a plush 'furry' side to sit nicely against the skin). I will evaluate this, make the necessary adaptions for my next pair and duly report back. Over.