Hi there,
To be honest i wouldn't go to V8 or Turbo project with badget which you have.But it's me.It all depends how much you can do on your own and if you have a place where this work can be actually done.Onece your Z will have a different engine there are many other things which you have to update to keep everything right.Such project starts look like snow ball:new engine,new suspension,new brakes,new cooling,updating interior, ets.I just think if your goal is more hp and torque then you have to do everything right.Also it depends how rusty your car is and don't forget that early Z need body reinforsment.You have to keep in mind that doing swap can take your time and you can end up without your daily driver for unknow time.Having said this you will be the one who will make a decision.Just write everything your car needs and how much work you can do then calculate,if you see it's over then $2000 do yourself a favor and wait for better time, if you will be under budget go for it, people here will help you with problems you will run into. If you are not able to acomplish your Z dream maybe you will use money which you have for a downpayment for a new car, but keep your Z and slowly start to collect parts which are nessesary for update,look here and on other Z sites,E-bay actions for bargains and when you have nessesary parts start your project.If you absolutely have to have Z as a daily driver sell your ride add another 2000 and you will be able to end up with good daily driven Z, as long as you are in South CA you are able to find good 240-280 in 3K price range,or you can buy damaged 280zxt and swap engines.
All you have to do be honest with yourseld and calculate what you can do and for what you have to pay.All i can add every project will consume more money which you initially expected you would spent.Good luck!