The smallest dual band radio I have found is the now discontinued Yaesu FT-90. It has a very small remote head that will fit even the smallest places. Current small dual band radios are the Icom IC-208H or Yaesu FT-7800. Both have remote mount heads that fit in small places. The 208 comes with a remote kit and you can easily make a remote cable for the 7800. Some good super sick velcro will make mounting easy. I have also used some modified radar detector mounts to assist in mounting the remote heads.
I had the FT-90 and it was a good radio...kinda regret selling it now. I currently have a Icom 207 and 208, and both are very good radios.
As far as antennas, I would look at a glass mount antenna. Radio Shack used to make a pretty good one and I believe it is the same one now being offered by MFJ. They have been very good performers for me on several different vehicles over the years.
With these combos, I have been able to do installs with no holes drilled in the car, which makes significant others happy. Hope this helps.