Ok, so I picked up the cabinet today and have sat the tank on top, it fits perfectly. Also the black Perspex came this morning so I siliconed it to the weir box. I have been out and brought some jet black gloss paint that j am going to paint the back of the tank with.
Here is the tank and cabinet with sump underneath.
You can see I have had the centre piece of the cabinet between the doors made so I can take it out. There are 2 locating blocks and magnets top and bottom that hold it in place. This makes working on the sump a lot easier.