Hello and Welcome to the Forums
I am a big fan on the Chinooks, although I've never owned one- they did the "Blazer Chalet" camper as well as their own RV's up until about 2006
I would guess that your marker lights are a generic type. This may be a good chance to replace with LED for longer life and less current draw. Sometimes a large truck plaza will have a nice selection of marker lights- Flying J/ Pilot or a TA
Most of the RV stuff is probably that used on a million RV's so as your approach each appliance you'll be able to get help deciding whether to repair or replace if there is a newer better option available
with a new rig it can be a good idea to "practice camp" in the driveway to get a handle on all the systems. there you have access to all your tools and the internet if you need to look something up
We just spent a few weeks in WA and found some great spots in the Cascades, and along the coast
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