The pace of your 8 miles run is faster than that of your 3 miles run on Friday.
You can try a little faster on short runs.
Time goes fast. You only have four more weekends available for training. But I'm sure you're almost there. I just checked the course information. It appears to be a very scenic and flat one. Enjoy!
Inspired by you, I'm thinking of runnig a full course in December.