Micamold Tropicaps
 

My Setchell Carlson has several Micamold Tropicaps in it. I tried researching them on the internet and got conflicting info. They're obviously plactic on the outside, but are they paper or film caps on the inside? Are they reliable, or should I change them just like paper caps?

I would change them.

Change them! A lot of those plastic cased paper capacitors were prone to being more leaky and/or blowing up than the older wax capacitors of the '30's. I replaced a couple of those in a radio awhile back and both of them were leaky to heck and back.