Bang and the engines gone

Ok i think ive just about had enough now, engine went pop weekend before last, my fault entirely, i missed a gear out on track 4th to 3rd at 130ish mph, smoke everywhere, i think its melted the rings amongst other things (i ve not pulled it apart yet), bottom end seems ok though, no knocking, but lots of piston slap.....Do i re build again or turn gay and stick an sr or ls1 in it?