This detail set from Aber is available directly from Hobby Link Japan  

Click on images below to see larger images

This set includes photo etch parts including the floor for the 1/35 Sd.Kfz. 251/1 Ausf D from AFV Club.  This set focuses on the interior and includes plenty of parts that will nicely dress up the interior on your model.  the texture on the floors in this set look great and can be seen in the photo below.

There one page of instructions with line drawing pictures that explain the process to using this set and it does not look overly difficult.

You will be required to fold the photoetch in this set, but if you have one of the Hold & Fold photo etch benders from The Small Shop, then this will be an easy process.    They have a variety of benders for sharp corners as well as rounded corners and in many different sizes.