Ken...thanks...lol, but yes as WhiteKnuckle has found out, trying to form around two objects at the same time can be challenging, several factors play into it, leading one is how thick a leather you are using (also who's leather is key too) I stopped taking combo orders as they are labor intensive and just a pain to make as well, frankly.
For some other tips that you may want to consider to use in this build,
check this tutorial I made a while back
So there are no tutorials regarding making them, but here's a rough idea on the process;
I take some bubble wrap, small bubbles, to use that to figure out how much leather I'll be eating up, the bubble wrap will provide a close approximation to the leather thickness and you can easily bend it around your objects, usually a knife and a light.
Now my sheaths also have the belt loop folding down behind the sheath, so it's part of the main piece of leather you would be using.
Then the side that wraps around the knife and light will be wide enough to reach around and over the two items, AND end up wrapping all the way around the back where it will be glued and stitched behind the knife.
I form the knife first, leaving the one side to just extend out, and deal with that after I have the knife portion formed. Once the knife side is formed, I will glue it down to the back side, punch in my stitching holes down the center and around the bottom and stitch down the center, stopping near the bottom.
That is just to HOLD the leather in place while I then start forming the light section, it will wrap tightly around the light, pulling the 'tube' around to be close to the knife, keeping things nice and compact as possible. A lot of the smaller lights have no contour, so on the one shown below, I glued in a small piece of leather so the light comes down and hits that and can go no further.
Once the light side is formed, I'll rough up the leather on the back side, removing the stitches first as they did their job keeping things together up to this point. I'll glue the light's wrapped around piece to the back side, and then punch in my holes yet again, just through the same holes that were there and THEN do a final stitch down between the knife and light. When I get down to the end of the light's holder, I'll stop and fold the belt loop flap down behind the knife sheath so that it can be glued to the bottom of the sheath, then punch in those holes and finish sewing around the bottom with a couple back stitches to lock it in place.
hope that helps and makes some sense, but as I say, it's a time consuming thing and often tricky in nature, I'd recommend leather about 6/7 oz thickness and of course I would suggest Wickett & Craig leather, just good stuff.
G2
Edited to add: Welcome to Bladeforums GiraffeHooves, those look like a lot of work as well, something more suited to a sewing machine but those can be pretty pricey. One thing I'd recommend is when you end your stitches to just back stitch two or three holes and trim the thread off, it will lock in place pretty well by just that.
Thank you for saying it looks good!