firewall questions

[IndyNova]

So as I begin my build, I am wanting to smooth the firewall on my 70 Nova. I am going to be cutting out my own panels from 16ga steel, and was wanting to fill in the factory steering hole. I have thought about going with an aftermarket column and was wondering if it would be easier to fill the area from the factory and re-cut a smaller opening for the new column, or just leave the factory mounting location alone and just live with the opening as is? Also, if anyone has any pics of the hidden wiper motor, that would be cool since I want to do that mod also. Thanks guys