This is from a 2000 Chevrolet 1/2 Ton 2wd truck with a 5.3L engine & 4L60E trans. Other years and models may be similar. If any wire color does not match what you have, email me and I will get you the correct information.
Looking at back of Connector C2
Use this info to use the stock underhood fuse block. C2 is connection for engine wiring harness, other then that only 4 other connections needed, they are listed below:
C1- B11 - RED this wire feeds 12v Battery+ to ignition switch, hot at all times.
C1 - A9 - PINK - this wire is FROM ignition switch, hot in RUN, START. This powers up fuses on block.
C3 - F1 - GRAY - Power feed to fuel pump.
In addition to those connections, you need to connect C100 pin C, Pink, to 12v+ RUN/START source. This wire feeds the Transmission Solenoids and PCM. The fuse for this wire is NOT in the underhood fuse block. The fuse was located in the underdash fuseblock in the 99+ pickups. You need to use a 10A fuse for this wire and hook to a RUN/START 12v+ source. This wire runs from C100 Pin C to Underhood Fuseblock C2 - E2. Inside the fuse block, it turns around and comes back out on C2 - F2. F2 then runs to the PCM and Transmission.