Dave, PAW and Summit sell 3-into-1 headers by Hedman (#69310), but they are for '63-'79 230-292. PAW sells them for $159.95, Summit is $151.95(I think). They are full length with nice thick flanges. Hope this helps.
'68 C-10 - 250 with Edelbrock 600cfm 4 barrel, Offy intake, Hedman headers and true duals, HEI, MSD 6A box, relocated gas tank
Soon to have: T-5 tranny
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