Looks good, made something really similar for my Leon last year using and old gauge pod and some fibreglass and a bit of filler. Turned out really well and much more robust than the plastic inserts that costs almost £50. I basically removed the vents, put some clingfilm over it, inserted a chopped down pod then fibreglassed it in place, sanded it down, bit of filler, prepped then satin blacked!!
The autogauge was just a temporary measure, got a black SW gauge in there now.
If its simple to make then why not make a few and ebay them, you will almost certainly make a few bucks.
