I also thought this one might be an option. It is shorter than the Associated tank but has a bigger foot print. The real problem is the price!
One thing I am doing with my Spada is to use smaller servos. Will give more clearance between the stock tank and the steering servo. I ordered the Futaba S9650 Mini Digital.
I wish I had a good LHS for shopping parts, but sadly I don't. Hobby shops in the Atlanta area have always sucked bad!!!