Q1- The bolt patterns are all the same, as long as the headgaskets are the EJ22t (for the water passages) you should be good. Some say that the P2 sensors or trigger signals don't work with the P1 ecu. As long as you use the cam gear from your car and the crank gear from your car, your ECU won't know the difference. I just tested this, and the sensor does pick up the P1 signal, so as long as the connector fits on the cam sensor (I'm pretty sure it does but haven't done the final test yet), it will work. MAF/MAP motors don't make a big difference for the heads.
Q2- Pigtails are connectors cutout of the harness with a length of wire left on the end. Basically you cut them out of another engine harness, cut your existing ones out of yours, and then solder the new ones in.