"Finally, there is the infamous English word 'Aztec'. The opposition of
/zt/ and /st/ remains." Richard WORDINGHAM, ENGLAND

In the normal procedure one has to contrast two words. Is there such a word
as <astec / asteck / etc.> that can be contrasted with <Aztec>?
I am pretty sure a fairly large number of native speakers of English
pronounce it ['?aes tek], and few notice the difference.
On the other hand I think that those who pronounce it properly
(unconsciously) treat it as a compound : az + tek, and align its
pronunciation rule on that of such compounds : backlash, hairdo etc.
My opinion is that such compounds are run on two trochaic feet - word stress
being generally on the first mora of the first item - as opposed to base +
suffix derivatives that are run on a single trochaic foot, e.g. bullock,
speaker etc.

Jean-Paul G. POTET, FRANCE