If you want to service your transmission, there is a few tricks about going about it
Just need to borrow my cousin's special torque wrench and you get yourself a gasket kit and I'll come around.
As for other bits like filters and leads, do you know how long ago they were replaced? Might be ok.
Do you know if the motor had new lifters installed? If they wern't replaced at reco then add that as another thing to waste more money on
Maybe take the head off too and replace the head gasket
As for the brake system, I can help you out with that too. A good refresh of brake fluid would do it good.
Man I love these old motors. They are so damn simple to work with. You almost can't go wrong. Give me a shout some time