5-speed options

True... If your not launching it like a top fuel car than it might last longer...
How much are you looking to spend on this whole conversion? I would say that is a good place to start planning if you have a budget.

To some degree depends on the feedback I get here.

I need to get an idea on costs for such a project.

To be honest I'm leaning towards the TKO 500/600, some guys over at moparts have done a few using a scattershield with the bearing retainer turned down. Simple enough and I like using the stock clutch linkage.