Changing servo on Team Durango dest210 rtr

[Icemudd]

Heya- dest 210 comes with this http://arrma-rc.de/part/AR390133 , I was thinking to upgrade it to http://www.arrma-rc.com/part/AR390136 but problem is that the metal gear is slightly bigger than the original so it doesn't fit in http://www.team-durango.com/part-inf...artNo=TD320162 .. Can anyone give an idea how I can use this new servo or do I just have to use the old one?

Thanks in advance