Tony71502

Injectors will be too small for a blower.

89LX Coupe

It's not too bad of a set up for a budget build. If you could try to swing the cash for a used set of aluminum heads you'd be much happier! but if all you can afford is the iron gt40 heads then try to find the regular ones and not the P heads so you can use your headers and not burn plug wires left and right.

Get 1.7 rockers for it and that should help the hit of the cam out too just get upgraded valve springs for the heads. Use the stock valve covers like posted before and take the baffles out of them (both covers). If you could find a 94-95 cobra intake that would be best and it'll go with your parts well too. I don't see where the 75mm throttle body would be too big but 70mm would work fine too just gasket match the opening on the intake and get you a bigger maf as well.

Get a o/r mid pipe or one with hi flow cats have 3.73's to 4.10's installed if it hasn't already been done I'd recommend an adjustable fuel pressure regulator when you have everything apart along with a fuel pressure gauge. The stock injectors are fine for now but when you go to put a supercharger on they will be too small and at that point just upgrade them.

89LX Coupe

That should give you a decent jump in power over stock depending on how well it's dialed in and if you go and get it tuned I could see you making 250-270ish to the wheels on a dynojet.

Venomantidote95

Most supercharger kits will give you an injector option, stay around 10lbs and you will be fine!
Before jumping to boost or power adding do your basic bolt-on upgrades first! If you seriously plan on boost choose your upgrades accordingly!