Fogging inside of front headlights

I have 1997 ply voyageur where the inside of the front headlights have a film of some sort, it makes the headlights really dim. I did put in new
lights last year. I have read in one post here about taking the lens off, drilling a hole in the lowest part and resealing with a clear silicone. Anyone try it or got any suggestions? I have heard that new headlight assemblies cost around $100 each!!
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
Add image file
Upload is a website by car enthusiasts for car enthusiasts. It is not affiliated with any of the car or spare part manufacturers or car dealers discussed here. All logos and trade names are the property of their respective owners.