Here are some examples from a horn player in a tejano group:
https://www.youtube.com/watch?v=9cYw9jdSS8s Instrumentation: Horns (somewhat covered by one of the keyboard players in this live example - plus the tenor lead)
Accordion (diatonic, button - similar to harmonica - carry multiple keys of accordion depending on the tune's key)
Keyboards (which cover horn, strings, guitar, synth sounds, electric piano, etc)
Bass
Drums (generally an emphasis on the upbeat)
Vocals/harmonies
https://www.youtube.com/watch?v=r4-IGnQGU18 Similar instrumentation - but with actual guitar (distorted, lead and clean rhythm guitar w/primarily an upbeat figure) Lead sax here is an alto.
https://www.youtube.com/watch?v=BcCE7gaUxOUhttps://www.youtube.com/watch?v=tF9oyaAA4S4 Similar instrumentation - add a more full horn section with trumpets (2+), trombone, tenor sax, bari sax (or alto sax)
https://www.youtube.com/watch?v=jEs02X74gAM Similar instrumentation - add a more full horn section with trumpets (2+), trombone, tenor sax, bari sax (or alto sax)
https://www.youtube.com/watch?v=fHqfDYs55Qw Same group as above, different style
https://www.youtube.com/watch?v=scHMPQZG97A Different group - similar instrumentation with more full horn section.
https://www.youtube.com/watch?v=rU9IwVHo2Ik As above
https://www.youtube.com/watch?v=HxQ6KwVmXI4 More keyboard centric - subtract large horn section and subtract accordion
https://www.youtube.com/watch?v=lqxIPMxQk8g Similar instrumentation as above
https://www.youtube.com/watch?v=OoS3Rim5kVk Instrumentation for this tune varies - later versions have more keyboard and two trumpets.
https://www.youtube.com/watch?v=ax4tmeB9IQg Back to Latin breed - distorted guitar + full horn section
https://www.youtube.com/watch?v=h-1GeOwo6p4 Ballad - more trombone featured
https://www.youtube.com/watch?v=Tc5Fb5Ze_UA Horn section, accordion, percussion
https://www.youtube.com/watch?v=jm1ah5j_f5A Full horn section, no accordion
https://www.youtube.com/watch?v=mDUo2X3d-fg Accordion, alto sax (not as full of a horn section)
https://www.youtube.com/watch?v=JwrtIFJXkXchttps://www.youtube.com/watch?v=9VhNi9A9Dkg Accordion/Bajo Sexto + (alto sax, keyboard used sparingly)
https://www.youtube.com/watch?v=GOohegkcZpAhttps://www.youtube.com/watch?v=0Xy_Qpk4qXc Full horn section (trumpets, saxes, bone), keys, accordion
https://www.youtube.com/watch?v=7PgPaeyDtJohttps://www.youtube.com/watch?v=xzgx3AcMl3Q(
https://www.youtube.com/watch?v=7Qt43UpdakY live version - accordion, guitar, keys, alto sax)
... More in the Latin vein:
https://www.youtube.com/watch?v=xnitHzpPbDE Full horn section - no accordion
https://www.youtube.com/watch?v=iweW1evEr5U (above is cover of Johnny Martinez - here)