High oil pressure

When I start my 1979 Chevy Scotsdale truck with a 256cc engine, the oil gauge jumps to full pressure, 60 on the gauge, and trys to bounce higher on acceleration. Although the oil smells hot, the temp gauge registers normal. When I checked the oil level after a jaunt around the block, smoke came out of the dip stick tube as I removed the dip stick. The oil level was OK. 45,000mi on the engine