turbo motor

[72nova]

I am considering starting a turbo project. I have no experience with them but am wanting to learn more about them. A guy I work with has a 402 bbc for sale cheap. I am going to get this motor regardless. I've been looking on ebay for a used turbo and need to know some things. Their are some that say minimal endplay, no end play, etc. What is the least endplay i should consider before buying? Am I just wasting my time looking at these? the ones I have been looking at are off of powerstroke diesels. Would I need 2 to make this project worthwhile? I am not expecting 1000 hp, but just wanting to learn more as I go, before stepping up to a high dollar turbo. Is this worht consdering or am I just wasting my time trying to do this? I know the details are sketchy but any info would be great. If only I could afford a Nelson motor this would be easy.

[Madspeed]

If you throw your money at something you will later change then your throwing money away period.
If this is the case I am in need of unesceserry cash you might not need =) for my twin turbo application
and if you have enough of it ill throw a NEW 496 inch big block chevy with aluminum heads back at you =) (as I have an awsome one for sale atm)