Pretty much definetly worn engine mounts. I changed them on my 16v and gearstick doesnt move about much now (also less clonks and car feels generally tighter for it). They are cheap apart from top right hand one which is reno only, and about 70 odd squid. RT one might be less, but Ive never looked at an RT so dont know, but it will be mounts on an RT causing this also. Gearbox one, is the main one in preventing, too much radial movement in powertrain. Hill power do an uprated one, which sound like a wise investment. They are not as difficult to change as you might think (I certainly expected more hassle), give us a shout if unsure about any of it.