How to mod my RP

[Antti]

Where in this layout of my 36 watt Richie plexi can i find components to
change it for less high end?And witch component to change for more bass?
And wich values for the ne components?Any ideas?

Thanks!!

[Antti]

Here is a URL to the layout.

http://i140.photobucket.com/albums/r3/a ... iatone.jpg