So I replaced my head unit today.  What a PITA (I've got the MOST bus).  No harness adapters that I could find so I basically had to hand wire everything.
Ordered an antenna adapter off Ebay and low and behold it arrived as I was doing the install.  But....it doesn't fit.  Anyone know where I can get the right sized adapter?  Google usually brings up one similar to the one I got.

Got this adapter off Ebay.  Other end is fine.  This end is to big.

Here's my factory antenna cable (plugs into the back of a CDR23).  Where can I get an adapter that fits this little guy?