, yes I did some experiments with some other bogies I used for a version of an MJA and they seemed to work OK. The material is really quite flexible so if it was just a flat plate then I'm pretty sure it would deflect under load, so the couplings would tend to lift or droop under tension. To try and stop this I designed a flat plate that a Dapol NEM Pocket could be fixed to.
Did you have a use for these bogies in mind? I would be happy to look at this for you, I would just need some details about the wagon and wheel size you were looking at so I could work out the correct coupler height.