4.5 carb and distributor conversion

I am new to this site and am looking gfor some help on converting a 4.5L to carb. I have it in a fiero and want to convert it to carb and know the dist. has to be converted. I found out that you use the internals from an olds dist. but cant find out which cars or years or engines to get the olds dist. from. Can anyone help me on this? Also I think the 500 cfm holley 2 barrell is what most run but has anyone ran a 600 holly 4 barrell? Thanks for any help you can give! Phillip