Most every state has restrictions on how much tint may be applied to a windshield. Some windshields are already tinted to the max allowed, but maybe your '95 is not.
Tinting does not do much for heat gain unless the "tint" is reflective on one side. A dark tint merely converts the sun to heat right on the glass, so you need to reflect the sun away rather than just stop it at the glass.
When parked, you can put one of those large reflector shields on the dash inside - they help quite a bit. Many RV stores have a super-large size for motorhome windshields.