Doesn't sound good, possibly a head gasket issue.
Who did the engine?
Have you replaced any sensors, can you be sure the gauges are reading correctly?
As already stated, what about the thermostat, has that been changed?
it is unlikely to be BOTH, bad guage and thermostat, causing it to overheat, normally you'd have on or the other, TBH it sounds like something more sinister like the HG or other issue.