When you say 'stock manifolds', do you mean logs? There is nothing better than a Poncho engine with long branch manifolds. (LBMs) RARE makes an excellent repop of the original LBMs. Butler sometimes sells the RARE ones for less than RARE has on their website. There are other companies that also make repop D-Port LBMs, but they are not as nice and clean as the ones RARE sells.
You can also get the hardware from RARE, and have them ceramic coated, although it only lasts 5-10 years.
I used to be indecisive. Now I'm not sure. I feel like I am diagonally parked in a parallel universe. 1968 400 convertible (Scarlet) 1976 T/A - 455 LE (No Burt) 1976 T/A New baby, starting full restoration. 1968 350 - 4 speed 'vert - 400 clone (the Beast!) 1968 350 convertible - Wife's car now- 400 clone (Aleutian Blue) (Blue Angel) 2008 Durango - DD 2008 GXP - New one from NH is AWESOME! 2017 Durango Citadel - Modern is nice! HEMI is amazing! 1998 Silverado Z71 - Father-daughter project 1968 400 coupe - R/A clone (Blue Pearl) (sold) 1967 326 convertible - Sold 1980 T/A SE Bandit - Sold