That's really about all the valve body will do for you, so it sounds like it's working as advertised. As for another forward gear, you'd most likely need another transmission like an AOD. I think someone sold an add-on part or a lock-up converter or something that gives you another "gear" but I could be mistaken. I haven't run an automatic in my car for quite some time - like around 20 years - so I'm not up on everything there is to know about them any more. The closest I've come is an 84 convertible that I transplanted a 5.0/AOD/8.8 combo from a Lincoln Mark VII. I only ran the car for maybe 2 years before I had to sell it, but it was a fun little car! I left the transmission completely stock, only changed a seal or 2 because it was leaking all over the place. As for help on the top end, a quick and easy way to do that would be swap a taller tire, but you'll lose acceleration from the line that way. The opposite is true if you use a smaller diameter tire. It's all a trade off in that regard, same with swapping rear gears.
