I just moved two years ago and had to sell alot of my stuff and not wanting to pay storage fees at my new location. I went to sale sites and whatever they were asking I cut the price in half but no bickering on the price after that. I sold almost everything I wanted to sale in a short time. I bet those who wanted CRAZY money for their STUFF still have it. I did try to weed out the flippers and did refuse some buyers. I have now moved and have a two car garage with plenty of storage space but do not regret selling anything because they were parts that I would never use myself. If you don't need the STUFF sale them and let others enjoy. Per the OP question, my thought is if someone needs just one gauge sale the gauge at $50.00 but for the complete unit $100.00 to $200.00 depending on its condition. Yes, if you parted it out you may get $500.00 but how long till you sale it? Sale it complete and be done with it.