My heat sink fins are three inches deep. I'm thinking that I can take my
dremel and cut into the fins so the fan or fans will be inset and out of
harms way while still protecting the unit. I use mine at less than the
maximum power anyway so I don't have heat problems in the house, but during
the summer in the truck the temp can get up there in a hurry.

I find one minute of AM makes my amp hotter then 5 minutes of sideband.
The radio on the left runs FM. That's a constant 5, 10 or 50 watts.
I wish it had another mid power setting at 25 watts. Sometimes 10
isn't enough and 50 is too much. It's also been modified to do MURS.

The 667 has a few fins pushed over to grab the course pitch screws in the
lower mounting holes. The finger guard is attached to the upper holes.
That amp is strapped and will draw a good 90 amps, about 1,250 DC watts!
That fan turns on when the power button is depressed. I switched the one
on the Icom. I'm a real good sandbagger sometimes and cold air will blow
after a few minutes of shutup time.