Q1: yes. if by that you mean the T50 in the AE86.
Q2: yes. by no means cut the firewall at all. your smoking your boyfriends arsecrack if you do. you can buy dizzy re-mounting kits, or better yet run individual coils from a GZE instead of cutting the firewall. you will also need a programmable ECU if you like things like a speedo and working dash.
you will also need to do something about the water outlets at the back of the head. this has been covered many many many many many many many many many times before.
Q3: couple of options. get a bigger intank pump from a say a toyota avalon or walboro, bosch etc. or use a external pump like a bosch or VL commodore pump.
Q4: by this you mean exhaust manifold? if so then yes.. you can get a TRD copy manifold from kaizen garage for a good price that will fit.
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