Musical? I'm sure glad I didn't see that version! I really enjoyed the movie but if they'd broken into song I seriously doubt I'd be saying the same thing now.
Woman, man! That's the way it should be Tarzan.
[Tarzan and his mate]

This is a very late reply. I just wanted to state that a musical "Tom Jones" has been written! I found the Broadway cast recording in the Seventies, on LP of course, and I love the songs!
Oddly, I can find nothing on-line about the stage musical, so I'll have to go through my albums to see if I can glean information, which I'll try to add here.
I recall that I found the cast album for "All in Love" at just about the same time! That's another I need to revisit.
EDIT: I reworded my search and found information!
http://www.worldcat.org/title/musical-version-of-tom-jones/oclc/5502338
Amazon has it!
http://www.amazon.com/Original-Musical-Recording-Version-Jones/dp/B003IDQ6EK
It's only on vinyl, but I'm lucky to have a number of record players.
(W)hat are we without our dreams?
Making sure our fantasies
Do not overpower our realities. ~ RC

I agree!

It was done as a stage play in the 19th century.