K&F geared head (GD3W) incompatible with large/irregular tripod base plates

I purchased the K&F geared head a couple of days ago as it was on a good price reduction in Amazon. I was hoping it would fit onto my Manfrotto 055CXPRO4 tripod. I removed the included Manfrotto head leaving the plate (incorporating a protruding bubble leveller).

Unfortunately, the K&F head can't fully screw on as the 2 lower gear assemblies keep catching on that protruding bubble. I though I might use an EZ-Leveller II that I use with my Fanotech nodal assembly, but no - that's also an irregular protruding shape. This issue is going to apply to any base plate that's wider than about 5.3cm.

Am I daft, lol? ...have I missed something simple? Maybe there's a simple 'spacer' solution while leaving enough thread to attach the K&F head?