Great plan and yes that's bound to fix it
If I can just add further strength to a point made in that other thread... When cleaning the headlight lens, DO NOT attempt to clean the reflector or shiny decorative elements - no water, no soap, no cloths or tissues - as they are black plastic and have the most delicate metallised coating imaginable. If they are tarnished - live with it - it looks better that way than with ragged black scratches and patches
Cleaning the glass lens (after removing from the headlight with a heat gun) is fine as it is glass and will come up crystal-clear after a scrub in hot water and clothes-washing detergent. Removing and cleaning the projector lens is OK too - leave it in the metal housing. Pop the housing off the balljoints after removing the shiny decorative element Very carefully (and place it somewhere safe). Perhaps wear gloves when pushing off the balljoints, I gashed my fingers on sharp edges when it let go with a BANG and the plastic frame landed on the floor breaking one of the projector housing mounts, the headlight unit also flew off the table, knocking over a vase which sprayed water across the shiny bits. Wiping the blood and water off, I scratched them.
I found gooey grey speaker sealant is a perfect replacement for the stuff that holds the lens on, but I don't recommend trying to replace this (re-use the original instead) - two reasons: 1) it was a helluva job digging and cleaning the old stuff out, and 2) the lens cracked down the middle when I refitted it. I probably put slightly too much sealant in the groove. Of course this was the other headlight with the still-good shiny bits
The price for re-metalising the shiny bits ran to three figures and I was quoted a month's lead time, as the one place that does this in NZ is flat-out busy making shiny plastic coffin handles for export to the USA. I found one replacement headlight in NZ but it was $800 (£390).
So I have to live with my mistake, but I hope you can learn from it