Paul, I went to soldering school in the mid 80's, and I became a soldering instructor and have written articles and lectured on the topic in the 90's. What you accomplished is no small feat! SMDs require specialized equipment, training and techniques that require years of experience to acquire. The fact that you opened up the machine and successfully replaced an SMD and didn't damage it with excessive heat, or damage the PCB tracks/pads, is kinda like performing a successful surgical procedure without being a surgeon. And, the fact that you had the foresight to purchase and practice with a kit speaks volumes with regard to your intelligence and resolve. You've certainly earned my respect!