Nice install!
Ya, the 8" box has a lot more volume as well.
As an aside: I did notice that the difference in using the stock radio amp pass-thru radio harness in my '97 vs. the non-amp setup just using the wiring in my '00 resulted in a lot better sound quality as far as bass response in the '00. In my '97 I had the gain set at about 90%, Low loudness, bass +1 or +2 on the deck. Now, I can run the gain at 50-55%, Low loudness (I know it's not the best for the sub...) and bass at -1 to 0 on the deck and achieve the same sound. I can't run it as loud as it was, there is too much bass. (For me anyway)