As pictured there should be fine. if it's getting hot you may be trying to run it into a low impedence it is not rated for, or driving it too hard.

Although amps have gain controls running it at max with a strong signal in is like driving a car at 5,000rpm, in theory it is capable but after a while you are likely to encounter problems.

Thats why it's often good to have a more powerfull amp than you need so you have plenty of headroom.

Again much like a car, i love having 400rwkw but dont use that everyday, just means whent he car is producing 250rwkw it's only ticking over....

A simple test at home on what running the gains to high on an amp causes.
If u have pay tv turn the volume all the way down on the set top unit.
Then turn up the tv to full.
You will now hear alot of hiss from the speakers.
Now turn up the set top unit just a little.

Now doesnt that sound awful!!!!

Picture the tv as ur amp in the car and the set top unit the Head unit.
All that running gains to high on the amps causes alot of unwanted noise and a sure way to blow amps and or speakers because its all running too hot.