Thinking about shooting paper negatives in an sx 70

I am thinking about shooting paper negatives in an sx 70. I was planning to do this by putting gaffers tape over the light sensor to force the camera to do longer exposures. I am planning on putting the paper in an empty cartridge. Any advice?

Except for the speed of the paper, you will not get other answers here than in your other thread.

it works, have done it. It´s tedious however and not suited for more than an experiment imho.