Speaker Improvement Needed

I have a set of Canton 6.5 inch splits that I have recently moved from one car to my 1983 280SE.

In their original location (an old Rover P6B), I cut nice big holes in
the front door and front door trim and mounted the drivers directly to the door.

Unfortunately, in the Mercedes, the doors are a bit full of window winder motors etc and the door trim a little complex to provide for easy direct mounting. My local stereo shop made a set of custom pods to mount against the door trim. The position of the speakers relative to the listner is similar to their previous location, except about six inches higher.

The speakers are powered by the same amp as in their previous
location.

Performance of the speakers has declined noticeably. Bottom end and mid range dynamics seem to have suffered most. THe speakers, in their original location, were awesome. In their new location, they are merely quite good.

Options that have occured to me include:

. increasing the solidness of the pod mounting to the door;

. porting the pods through to the door cavity;

. taking a saw to the door trim and door and mount the speakers securely to the door;

Any thoughts / comments / suggestions much appreciated.