EGT should go in the exhaust manifold before the turbo in the rear runner. The manifold IS divided so don't drill in the middle.
Trans temp you can order a line from Dodge or NAPA that will replace one stock trans cooler line, the replacement line will have a port in it that the sending unit can go into. Barring that you can just drill and tap the pan.
Boost there is a plug in the side of the head below the intake, I believe it to be a 3/4 pipe plug, just pull it out and adapt to whatever size line is needed for the gauge.