The 1200 lives again! I changed out the head from a k321 I had sitting around. If it blows again I'll have the head and block milled. Gasket looked like it blew on the block side this time. I did reference the manuals section for torque specs, etc.
On the rectifier issue. I didn't check it like Steve suggested, I will though. At the battery, my digital meter was spiking around, showing up to 22 volts at high idle with a minimum of 14. I checked the new one and it spiked around a bit too, but only went up to 17 volts. What I'm referring to as 'spiking' is the numbers I see show up on the meter. I may just go pick up an analog meter and review it as well. I found another used rectifier on that same lone engine and popped it on the 1200 with the same results as the new one.