another th350c wiring question

[big_b]

ive done alot of searching and confused myself even more.
im putting a 305/350c motor back into an '83 chev.

i have the wiring, brake switch adaptor for the lockup and vacuum switch on the firewall.

the trans has a 2 prong plug on the drivers side. on the passenger side of the trans there is another 2 prong plug that is different looking than the plug on the drivers side, it looks to be a pressure switch?

the wiring harness from the firewall for the trans hook ups has another inline 2 prong wire plug but i do not no where this hooks up to???

i want to hook up the lockup but i dont know what these other wiring connections do and how important they are to have opperational.

is anybody familiar with these transmissions and can help make the mud a little clearer for me?
thanks
i need to buy a manual.