Will,
My you are a busy Mudcatter. I just finished searching the forum and found the same thread Pete M. found. I should mention that there are several postings with slightly different chords in each, so I encourage you to read the complete thread.
You could have found this thread, too. What Pete M. and I did was go to the main forum page. At the top is a series of blue underlined phrases. We clicked on Forum Search. Then I typed "once I built a tower" (without quotation marks) into the rectangle labelled body. I chose those words because they are a consistent phrase in the song that is not likely to be duplicated in another song. If I used the song title some would have listed "brother" instead of "buddy" and possibly "spare me" rather than "spare".
You have taken the first step using a DT search for "San Miguel." Next step is a Forum Search and you'll be growin' up real fast.
The next step will be posting information you have to someone else's request or joining in some discussion on a thread.
I learned all of this from my fellow Mudcatters in the last year.
Keep on 'Cattin' and enjoy the song!
Roger in Baltimore