After 4 years of active RV travel, the shrinking and compromised vertical wall sealant needed to be addressed. It had lost its adhesion on many of the beads. After 2 days (10 hours) of physical hand abuse, I was able to remove all the siliconized sealant from the marker lights, tail lights, pass through storage doors, electrical outlet covers, front vertical seams, fridge access panel, and other exterior lights. It was not a fun 10 hours. I'm not sure why RV makers still use silicone. (Confident to say the $10 savings on a tube of silicone is the answer.)
After finally removing all traces of old sealant from the mating surfaces with the help of mineral spirits and denatured alcohol, I applied a superior product, Geocel Proflex RV sealant (link below). The Proflex is a little more difficult to work with but is substantially better.
Hint for a clean application: after applying the bead, use a high soap content bowl of water (dish soap) to dip your bead laying finger in to create a smooth finished look. Dip often (each time the finger is pulled away) and work fast. Practice a couple of times on some scrap material to acclimate to the "workability" of the sealant.
https://www.amazon.com/Geocel-GC2810.../dp/B001FC98X2
