I gave it another go at cleaning it up a bit better. Now remember the first recording cleanup I posted had the same sound twice, once forwards and once backwards. This time I'm posting it only as a forward recording.
The speed or pitch has not been altered from the original. The only cleanup done is noise removal, and running it through an Aural Exciter to try to bring back some of the clarity in the high frequencies during the cleanup.
I'm using Audacity as the base product. The Noise removal works by first isolating the noise component based on frequencies during the quiet parts. Once isolated it then subtracts this from the original while at the same time adding a limiter with an attack function. What that does is that during the quieter times it silences the recording to remove the remaining background. This is because in quiet parts the noise floor is much more noticed. So if removed it makes the entire recording seem cleaner.
Second, the Aural Exciter is a process actually developed first by the hit band "Boston". Its a process by which the high frequency sounds are isolated, and then the upper harmonics (double frequency versions) of those high sounds are added back into the original. This creates a crisper version especially on vocals, and makes it much more understandable by the human brain.
Here's the cleaned recording again Take 2: