I used the surround supplied to fit it to a mk6 and trimmed it down to the stepup roughing it down with a bench grinder then using a dremel with a sanding barrel until it looked nice. The surround from the mk6 in a mk5 has a smaller hole than the mk5 standard surround. I marked out where I needed to trim and started with drilling small holes to remove the majority of excess material. Then I used the dremel to get it right. To hold the two together, I used some waste plastic and melted some bridges to join the two together. Good thing is that I didn't need to paint it doing it this way and the join is on an edge.