I,m looking for a slicktop tahoe with the possibility of a swat skin, any suggestions 

 

I personally haven't put this into my game yet so I don't know exactly what the model looks like. As for a texture I'm sure you could find one pretty easily. 

There are a hella ton of slicktop Tahoes that I know of (Bxbugs123 over on GPM has about 7 at least uploaded on there), but I would suggest this Tahoe if you're looking for a tactical vehicle with professional lighting and good equipment: http://gtapolicemods.com/downloads.php?do=file&id=1579

 

For a marked unit, I'd definitely consider Lt. Caine's newest release, a great Dodge Caravan: http://gtapolicemods.com/downloads.php?do=file&id=2227 or a default Landstalker (slicktop, marked but can be made unmarked) from Lt. Caine's newest police default ELS V7 pack here: http://gtapolicemods.com/downloads.php?do=file&id=2226

 

I don't know about any good SWAT textures, because usually they operate in unmarked units.  I will make one to your specifications though if you need so.