Hello and thanks all for your such a great help.

We have finalised the circuit with 8V/3.5V supply and
the diodes which we will be using will be of 5A capacity, but the main problem is the regulators if we use have max 1A capacity (TO-3) and my requirment is 3.5 - 4 A, I got a suggession from somewhere to use a darlington pair between I/P & O/P to increase the current capacity.
Can somebody tell me more hints for calculations of them. Or some other way to increase the current capacity.

I am really sorry
I am going tooooooo away from 8052.

Regards,
sachin