Wireing on starter, 1997 chevy blazer 4x4.

The big red wire goes directly to the battery. Just replace it. The contacts on the starter may also be badly corroded and you may end replacing the starter as well

Large purple wire is your starter engagement wire, I believe you will have to tie into more than that wire to get your remote start to work properly, maybe get me brand and model number so I may research more and point you in the right direction as far as installation goes.

I had to take motor mount loose on that side & lift motor away from mount to get room to remove starter

Here's a link to the wiring diagram for the 1997 Chevy Blazer.

When you go to start the engine you are actually sending power from the ignition switch through a 20 amp fuse [crank fuse] then through the Park/Nuetral safety start switch and finally to the starter relay [located at the center rear of the engine compartment] This relay then sends a more powerful current flow down to the starter solenoid located on top of the the starter which then closes and allows full battery voltage from the large battery cable to energize and spin the starter. I don't think I've ever had to replace a starter relay on these but have replaced a large number of starters with bad solenoids and bad Park/nuetral switches. The "crank" fuse could also be bad but that is also pretty rare.

need a wiring diagram for a 1999 chevy blazer 4.3 4x4... had to replace motor and now the 4x4 wont work... anyone know where u can print off the diagram

Check this link and as you read a bit down,you'll see a further link to get the diagrams:
http://www.wiringdiagrams21.com/2009/03/02/1995-chevrolet-tahoe-blazer-electrical-wiring-diagram

need email address to send diagrams, need to know what parts of electrial you need

oxygen sensor should be located in one of the manifolds under the blazer it may have 2 you can see them they will be screwd into the pipes connected to exhust with wire out the top of them

There are no free full diagrams on the net, you need to charge and test the battery, clean the battery cables and run a voltage drop test as well, replace them if the are badly corroded. Kragen will test the battery for free.