Sent you a message with some reputation points.
Then realized you might not know how to find it.:stoned:

So, I'll repost it here.
I recommend reflectix insulation to line the inside.
It reflects 98% of the full spectrum without "hotspots",
And a small, oscillating fan is basic equipment for a small cabinet.
Hmm, this could get long.

Pictures will certainly help
Suggest that you click on my avatar.
That will take you to my photo albums.
There are glimpses of both grow cabs there.

I grow with targeted spectra.
I use only 2 colors of LEDs because energy costs are very high here, but my cabinet design will work with CFLs as well.

Probably need to be modified a bit to deal with HPS or MH lighting.
Tell us what equipment you plan to use and we'll be happy to help.

Aloha,
Weezard