Looking to buy my first 1970 - Need Help

[remist17]

Hi all:
I have been looking for about 2 years and been on here alot learning as much as I can. I final found a truck that I can afford.

Some questions:
1- The rear was swapped out for a mid 80's camaro with disc breaks. Assuming the complete rear was swapped that would mean a 7.5" 10bolt....
How would that handle the torque of a mild 350?
2- How do I get the replacement break pads? Just ask for the mid 80's camaro pads?
3- The 3 speed manual transmission was swapped out for a 4 speed. I thought he said a Borg Warner but could be wrong. Would I match the Clutch to the motor or the trans? I am assuming the clutch and pressure plate would need to match both motor shafting and trans shafting.
4- He said the windows are a little difficult to wind back up. Does the arms usually need greased on these or am I looking at repalcing them.

I know these are some stupid questions but never looked at a updated truck before...

Specs of the truck:
1970 Longbed. 350, 4 speed, power steering and 4 wheel disc brakes. All rusted sheet metal repalced. nice rims and newer tires.