First of all, I tried using the tires from the REAL NZ Omaka scenery but couldn't line them up, so Mike sent me some custom ones that I loaded with ease.
Then, I went to delete the original REAL NZ tires by clicking the 'select object' tickbox then waited for the EZ Scenery red crosses to lock onto the tires once I placed my aircraft next to it, but for some reason it won't do that. (It works with all the other scenery on my airport though)

Anyway, how can I remove these? Is there a BGL decompiler that will remove it in a .cfg like file somewhere? Also, is it possible to remove the autogen trees at the end of the runway?