No, there is not a way.
Which transformer model does he have? TF101, TF200, TF300, TF600, or TF700?
Android runs on ARM processor architecture only. Windows 8 runs on intel. Windows RT runs on ARM, but it is not available (legally) for porting. It is only available for OEMs to install on their devices.
I highly suggest you highly suggest to your customer to sell his android device and buy a windows hybrid. There are plenty windows transformer type devices out there.
For windows 8, most hybrid devices run on the newest atom processor called clover trail. Don't let the word "atom" fool you. One of my devices has this processor (hp envy x2). I've written 2 windows 8 metro apps and published them on the store with only this device using visual studio, which anyone will tell you is a resource hog.
There are also i3 and i5 hybrid (transformer) windows 8 devices out there. For example, hp just came out with the HP Split X2 and is selling for about $600-something on Best Buy online. There is also the asus transformer tx300. Both these devices come with either an i3 or i5, depending on what you want.
There are also many windows RT transformer devices that run on ARM processors. Asus TF600 is one example.
Android is good for blogging, gaming, facebooking, etc. But it is lousy at productivity. Trust me, I tried for 2 years working with android. I tried using tools written by other developers and I even wrote my own tools to develop software on android. In the end, I just gave up and sold all my android devices and went completely with windows.