I`m hoping to start a major re-build on my 1986 s12 ca18et within the next few weeks and I`m hoping you guys can give me some opinions on the best way forward please

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I want to change the et for a ca18det and change the autobox for a matching manual box.
1). What`s the best year 200sx engine and box to go for and do you think all other parts (clutch cylinder etc) will be a straight swap onto the silvia ?
2). I`m looking for a reliable 300bhp, do you think this is achievable with forged pistons, reground crank, metal head gasket, etc, and should I opt for a set of steel con rods just to be on the safe side ?
3). Do the ca18det engines have bronze valve guides already fitted. If not, is this something to possibly have done ?
4). I`m planning on a hybrid T25/T28 turbo with 360 degree bearings, would this be the best option to go for ?
5). Obviously, I will be upgrading the fuel pump. But which are the best cc injectors to go for ?
I plan to use the car for a bit of weekend fun, so it won`t be my daily driver, but I don`t want some fire breathing, monster that`s undrivable on normal A-roads

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Do you think that the engine, turbo, and fuelling mods above are achievable on a budget of about 4 grand, or am I way off target

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If you can give me some opinions on any of the above, I would be really grateful

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Regards,
Ian.