Yes, the D6 uses standard rockers, pistons etc. But it's a challenge today to get anybody to make off the shelf headers. (Beg TTI maybe they will give in, they didn't for me.) You may have to make your own. Mopar used to offer intake and exhaust gaskets. Most people that port heads today are probably taking the intake port to a D6 size so intake gaskets shouldn't be hard. I have some exhaust gaskets that you could use as a template if you can't find any. The only other problem I see is back then people told me they were porous. I never ran any personally, so I don't know. You may have to put some ceramic sealer in them. But I think that is possible today. The D6 is certainly a good looking exhaust port.