When your done cleaning it, hold a shop lamp behind it and make sure you can see light through it. (or hold it up to the sun) Fine sand tends to get caught in the fins and is difficult to remove. Unless that's removed your work will be for nought. Also carefully check the support fins around the upper and lower tank outlets for cracks. Overheating will crack these areas first. If any cracking is found replace the radiator. If you just do normal driving and occasional trips to the track a stock radiator is plenty. Don't forget to replace the hoses and thermostat while it's all apart, it will never get any easier.
H
