Your truck is a good match for that TT. I think you are underestimating the weights. My Heartland TT was 300 pounds more when I picked it up new/empty than brochure/web site dry weight. Food, clothes, toys, chairs, etc all add up. Anyway, expect closer to 6k loaded with 750 pounds of loaded TW. I believe your receiver is only rated to 600 pounds without a WDH, so you need one. 750 pounds of TW will increase the rear axle by about 1050 and decrease the front axle by 300, so you probably want one anyway.
While towing a TT is a little different than smaller/low profile trailers, a cautious approach will build confidence. Learn how to adjust that WDH and brake controller. Use tow/haul trans mode. Keep it sloe, like under 60mph to start and under 65mph always.