Any guidance on my 1970 Duster plans

Nice car. Looks like F8 green. Stay with F8 green and add some white stripes.
@413 might have a good idea. If you truly do have a TA engine, it will likely be worth enough to buy a complete, running 340 or 360. If you find the right restorer desperate for a TA motor for their T/A or AAR, you might even have enough to buy a really good, running HP V8 with money left over (depending on what you paid for it, of course). Look into it.