Ok so I kinda built the panel and forgot to take pics so I will explain it in detail. You need a piece of solid(not thumb or finger joint timber) that is 18mm. The smallest I could find was 300mm wide x 600mm long. Also, a 1000mm long length of 18mm x 18mm square timber for the edges,(I only edge out 3 sides as one is side is fitted to the back wall of the enclosure). 2 packs of small brass hooks, pva glue, pondtite and stainer. Cut out a piece that is 300mmx300mm from your big bit of timber,This is your base. Now you need two lengths from the square edging to be 300mm long and one at 264mm. This will give you the edges. Now you need to pre drill these edges in two spots toward the ends so as not to split the wood when screwing together. Now, on the base you need to mark out where the edges will sit so take a pencil and mark the outline of the edges by sitting them on there. Draw a line from one corner to the other to form a diagonal x on the top. Measure and mark every 20mm starting from the edge marking. You should only need 16 hooks per line making a total of 32 hooks needed. Now pre drill these marks so you can screw in the hooks later. Now everything is drilled and ready, glue and screw the edges down to the base. Now after the glue is dry you can stain, dry, seal, dry and finally seal again for good measure. After its dried for a couple days to get rid of all smells you can screw in the hooks again, now for the ventilation of excess heat, put a screw in to each corner of the edging on the face that the tile will sit on and leave it about 4mm to 5mm from being flush in the wood. This will give a nice gap between the tile and the panel body for ventilation. If you plan on fixing the panel as a shelf you can drill holes ever 20mm plus a couple extra like in my photo to vent the excess heat directly under the panel. This seems to work quite well in taller enclosures. I think I have explained it pretty clear but if anyone needs and more help just let me know and I can take pics of the ones I am running now as I have both self mounted ones and ones on the ground level both in operation and both working perfectly