projection for uaxactun, guatemala

[TiborLieskovský]

Hello!
What is the optimal projection /coordinate system for Uaxactun, Guatemala?
We need to combine several types of data (measurement in WGS84, SRTM, ASTER GDEM) in a smart way.

Thank You for Your suggestions.

[GustavoCordero]

I'm from Guatemala normally use

WGS_1984_UTM_Zone_15N

Projection Transverse_Mercator

to be more accurate on the subject of measurements