Just thought I'd post some useful info regarding my single DIN conversion with OE parts. I came from an RNS510 for info.
I used a VW single DIN fascia (1K0857058A1QB £27.18) which has a storage compartment under. It's a one piece affair (no pop out pocket) and is the standard of finish you'd expect, particularly with the fitted rubber tray insert (1K08581699B9 £5.66).
I also used the Connects2 steering wheel interface (CTS VW002.2 with steering wheel lead CTKENWOODLEAD2 @ £43.98 for both parts) which correctly supports all buttons on the MFSW. It's worth noting that the original Autoleads part I used (PC99-505) did not support the right hand set of buttons correctly. It wouldn't show an 'audio' menu therefore when displaying any menu and using the up/down arrow buttons to navigate not only would it change the display it would change radio station, for instance, at the same time.
I know single DIN isn't everyone's cup of tea
but I thought I'd share this since I think it's as good as single DIN conversion could be and maybe this info will be useful for somebody who had considered it but dismissed it due to non OE finish with a poor quality fascia.