have an opertunity to purchase a set of nearly perfect, in terms of rust/pitting, 3725563 exh manifolds. problem, as my feeble mind sees it, is presence of rotary grind marks/scars on the top surface of each manifold , very similar to the grind marks present on midyear small block exh manifolds that were purchased over the counter in the 70's and 80's from gm and those currently being sold by such outfits as paragon. in terms of the midyear nors items, i believe the molds wore and the cast pieces from the worn molds were so scroungy looking the mfgr ground the parting line excess to enhance their appearance. anybody out there who bought the 563 manifolds just prior to their being discontinued and if so, are there rotatry grind marks present. better yet, any owners of very lo mile, rust free original manifolds with grind marks as described above.thanks, mikie