Have you decided on a heat source???
A bulb will dry the air out even more.
I dug up some photos of my old 40 gal tanks to illustrate the improvements I made.
First I put some door weather-stripping around the top of the tank.

Then just placed the precut plexi on top.

As you can see I use my old 40’s for rat tanks now. All the snakes are in racks(and doing better).
There are other things you can do to increase the humidity, put the water bowl partially over the heat source; home made Tropic Aire systems, damp towel over part of the top.
I tried them all, this cost me $5 US dollars and I never had a problem again.
One misting kept the humidity at 75-80 percent for a week.
And I disagree with Jason; you do need humidity even when they are not in shed. A minimum of 50 percent regularly and around 80 percent during sheds(however you attain it).
That’s my opinion.
Sorry I’ve been long winded lately, that’s not like me??
TomChambers