Welcome to the world of SOTA. It’s addictive.
You shouldn’t have any trouble with the FT-818. It has a Superhet receiver. The roll-up J-Pole should do quite well.
Since Brasstown Bald is the highest peak in Georgia, at 4,784 feet, you will be in range of many stations who monitor 146.520. From that elevation I have worked mobiles in Atlanta, with a HT and duckie.
Be sure to post an alert and spot. I will listen for you.
If you contact me via email, listed on QRZ, I have a quick-start guide to SOTA that I can send to you. I call it a SOTA Primer. I will send it as a PDF.