i have this Chevrolet astro bus from Canada,though originally it was bought from the dump yard but it was bought with named issues but getting to Nigeria here , it started picking up some faults,one of them which is the overheating ,i have bought a tokumbo new radiator and done whatever and now they are telling me it may be the top gasket and the thing is i dont want to tamper with this v8 engine without knowing the full fault,i have not seen a major Chevrolet mechanic but as well i want to ask any body related to this bus or is an engineer to help me out here.

The engine construction for Chevrolet doesn't give room for good ventilation and it usually doesn't come with 2 fans, so with the weather conditions here and the thermostat crap, hence the overheating over time. You should do a reconstruction to change the fan and deactivate the thermostat, lest the A/C might develop fault over time or better yet do a scan and ask the mech to explain everything diagnosed to you then you can choose the pressing thing to fix..