I won 2 ebay auctions today for 2 different?? timing chain sets. They are Melling double roller sets (2 sprockets and chain in each set). The numbers are something like 168-S and 168-SB. One is listed as 361, 413, 426, 440 and the other as 1972-1977 361. They look the same in the pics. The descriptions dont make sence to me but the seller said that is what the Melling description says. The first one doesnt make sense to me because it excludes 383 and 400, but includes 361 (B block) with the other listed RB blocks. The second set is strange because I am not sure they made a 361 in the 70's. Anybody know anything that could explain this?