Need a shifter boot for a modified set-up (photos)

[JerseyJim]

My rig has a DANA 20 with an Advanced Adapter with a C-6 tranny behind a 460 which is pretty long so the hole was moved back so the shifter would operate properly. Unfortyunately the PO put in another manufacturer's boot that just isn't long enough. I know I will need to fill in the hole but does anyone know where I can get a better fitting shifter boot? I'm really new at all of this.
Here's a photo link to the setup:
http://jpascale.photosite.com/scout4wdcaseboot/
Thanks in advance.
Jersey Jim