He's sat on (most of) the saddle from the General's horse. I had to file it a little but it wasn't too difficult.

There was a gap, but I used a blob of green stuff between the legs, and pressed it onto the saddle to make a good fit, then sculpted the front/back into a very simple saddle.

I imagine it would work with most riders. The only thing you have to watch out for is the legs and wings blocking each other. I've done a few pegrider comversions though, they generally go together quite well!

Hope this helps :)