Newbie hitch question

[Robokatz]

Hello everyone, fairly new to the site but hope to be a regular. My wife retired in August, and I plan to do so in July to start living our dream of traveling the country (and Canada) in our 1st RV. We just took delivery of a 2022 F350 Dually, my first ever truck, and early December we placed an order for a 2022 3231CK with pretty much everything including Cobalt paint and 1,200 watt solar. We have never towed anything before, so to be able practice first with a small rental 5th wheel, I just bought a BW Companion hitch, and mounted base in truck.

My question is setting up the vertical support arms. As you know, I can mount them so the RV is closer to cab a few inches, or closer to tailgate. Since truck is 8’ bed, is it safe to assume no issues setting up so RV is closer to cab (so cut down overall length) in terms of adequate space to turn etc? Also, there are 3 height positions, high, medium and low. My RV won’t be built until maybe April, but what height seems to be best for a 2021-22 F350 dually and a Montana? Should I just mount at middle height for now?

Thanks everyone, hope to meet many of you this summer and beyond.