Piaware SD Card Image Version 5.0:

sudo bash -c "$(wget -O - https://raw.githubusercontent.com/abcd567a/set-gain/master/piaware-img-5.0.sh)"   

Package Install Of Piaware And Dump1090-fa Version 5.0:

sudo bash -c "$(wget -O - https://raw.githubusercontent.com/abcd567a/set-gain/master/raspbian+dump-fa-5.0.sh)"     

Let's Do A Backup:

cd /usr/share/skyaware/html
sudo cp index.html index.html.orig

Let's Add A Cron Job:

sudo crontab -e

Paste The Following At The Bottom Of The File:

@reboot /bin/bash /usr/local/sbin/gain/setgain.sh

We Need To Add A Few Lines Of Code To The Following File:

sudo nano /usr/share/skyaware/html/index.html

Once Inside The File:
Press Ctrl+W And Type The Following buttonContainer and Hit Enter: 

Add The Following Lines Below, Above: <div class="buttonContainer">

<div id="GAIN" style="text-align:center;width:175px;height:65px;">
<iframe src=gain.php style="border:0;width:175px;height:65px;"></iframe>
</div> <!----- GAIN --->

Now Let's Do A Reboot:

sudo reboot