A few hard questions…I cannot work out what it is you want to achieve. Do you just want any kit car?Right to your questions.
1) well a fiero is a fiero…very few affordable cars have a mid-engine set-up…a fiero in America is around US$500.00 for a useable donor car consider importing one!!! If not you could try a MR2 mk1 mk2 mk3 but it will require significant rebuild…you will be better of to adapt a space frame or box frame chassis to accept you donor parts.
2) As far as I know there are no kit cars for a corolla but I could imagine (again with modification) that you could go for a lotus seven style replica…you do sell those in Australia. Have a look in a used car mag called ‘unique cars’ (I think!!!).
3) Honda civic dash…unsure but you might be able to fit a del sol dash some have been made in the past to look like F355 dash (not very convincing). Have a look at the modifying scene…SEMA or similar should be able to help you.
http://www.sema.org/main/semaorghome.aspx?ID=/content/SEMAorg/HomePage
4) Again as far as I know no kits for a ford falcon (assume you mean the Australian one here)…they are ok cars but WHY? You could use part on a space frame chassis but would require reworking again.
Now if I’m reading the writing between the lines you are trying to find a kitcar for a car you already own…that is a no no.
To have a good kit car you find a kit you like that is in your financial bracket (I always talk about money in these replies!!) and you build it using the recommended donor...manufactures have usually spent sometime working on their kits and know what they are talking about.
Anyhoo good luck
-Steffen