This page assumes you have Redhat 7.3 (or earlier)  (and accompanying Linux kernal), the Gnome desktop and you are using  dosemu-freedos-bin.tgz binaries from http://dosemu.org  There are .rpm packages for dosemu but these instructions do not apply to the .rpm versions. Other distributions of Linux should be okay to use with these directions, and as soon as instructions are available they will be posted.
Your computer must have at least 64 megs of RAM, a VESA 2.0 compatible VGA card and have wine (Codeweavers wine ) installed.  Although I haven't tried it, in theory, a Pentium/AMD 133 should be good enough.

If you are familiar with gunzip and tar you can follow the instruction in the next paragraph and then skip to the areas for configuration.

Unpack and tar in a directory owed by a non-root user. /home/<username> would be nice, but it would be better to find a top directory with its own partition.  If your Linux setup does not allow you to tar this file, then use the program gmc.  If you are running a much later version of Redhat than 7.3, you will most likely have to install it.  If you are using a Linux distribution other than Redhat, email me if you need any help at: stavka@rkka.org

Nominally, the command to unpack your tarball will be in the command line interface:

gunzip -dv dosemu-freedos-bin.tgz

Please note:  You must use the command line interface to decompress  tarballs.

The resulting file will be named: dosemu-freedos-bin.tar
Next:

tar -xvf dosemu-freedos-bin.tar

Some versions of tar may not allow you to tar this resulting file.  In this case, use gmc to tar the file.  In order to tar a file using gmc just highlight the icon, right click and select extract.

Now dosemu/freedos is installed!

Go to the dosemu.conf file in your DOS installation and
Edit the line: $_dpmi = (no) to read $_dpmi = (16000)
16 meg is the minimum allocation you will need to run Steel Panthers. Recommend allocating 48 to 80 megs

Installing the cd extension: http://www.shsu.edu/~csc_jhm/shsucd14.zip
Copy the file to the freedos directory.  Using gmc or wine unpack the file in that directory.

Make sure you see on your conf file the line:  $_floppy_b = ""        # dito for B:
make sure your autoexec.bat file has these lines:

unix -s DOSDRIVE_D
SHSUCDX /d:mscd0001, d
if "%DOSDRIVE_D%" == "" goto nodrived
lredir d: linux\fs%DOSDRIVE_D%
:nodrived

Make sure your config.sys file has these lines:

unix -s DOSDRIVE_D
SHSUCDX /d:mscd0001, d
if "%DOSDRIVE_D%" == "" goto nodrived
lredir d: linux\fs%DOSDRIVE_D%
:nodrived

Make sure you can make a desktop icon which points to the xdosemu program.
To make a desktop icon (Instructions for the Gnome Desktop):  
Right click on the panel at the bottom
Select Panel
Select Add to Panel
Select Launcher
Type in DOS as name
Type in this command: cd /yourdirectories/dosemu; ./xdosmu
Select an icon
Click OK
An icon will appear on the launch panel.  Click and hold down then drag icon onto desktop

Otherwise you can cd to /yourdirectories/dosemu
Then type this exactly:  ./xdosemu

If everything is done correctly a dos box should appear with the startup routine for dos.
Make sure there is a cd in your cd drive and while in dos type

 b:

This should be the cd drive

You will be unable to install any windows software using freedos, but any DOS software should install just fine.  There may be warnings that the  DOS version isn't high enough, but so far it hasn't prevented programs from installing and running.

Installing SPMBT:  
Use wine to execute the installation program.  Updates must also be executed using wine.  Make certain the installation is below your freedos directory, for example:

/home/<yourname>/dosemu/freedos/spmbt/

Installing Steel Panthers 3:
Steel Panthers 3 came out around the same time Microsoft Corporation came out with Windows 95.  Some CD releases have the DOS setup program, some have the windows setup program, some both.

The Windows setup program can be run under wine.  The DOS setup program can be run under dosemu. As with SPMBT, make sure you install to a directory below your freedos directory, if using wine or if you are just transferring a file setup from one drive to another.