Take a Tupperware tub of a size that fits will inside your super, put in a handful of straw, leaving some up and over the side, and fill it with syrup.
Then place two strips of wood on top of your crown board (the two bits fitted to the bottom of a frame are about right)place this on your board and then the tub on top of them, then put on a super then the roof, costs next to nothing, you get all the bits back when your done and does not drown half your bees.
One thing though; the day after you start feeding have a little check to make sure they’ve found it 99 times out of a 100 they do, but yours may just be the ones. If they don’t find it then dribble a little (and I mean little or you’ll drown some of your bees) down the hole in the crown board and up the side of the tub.