Never installed one, but a lot of guys with MSD DIS-4 stuff mount the box on the frame rail or the side of the core support. That seems to be a nice spot since it is all hidden.
I have mine hidden under the Rad Cover, using an existing stud thats already there. All you have to do is pickup the proper size nut to fit the threads on each side and you're good to go...
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With the cover in place - all you can see is a portion of black cable:
I mounted mine in almost the exact same place, except the 94-98 cars are a bit different so i mounted them on the same panel in the same area as the above pics, but flush against the front metal surface, in front of the radiator. I used 3M double sided tape. It's pretty much the only flat area, and the best area you'll find to mount your ballasts.