[68_chop_top]

Good luck with your build.
Mine is a 68 and I put a 496 in mine with a Tremec TKO600 5 speed.
I use a long water pump, factory clutch fan, tall valve covers, and power brakes.
I mocked up everything and did not use the forward frame holes and neither the rear frame holes. Drilled holes for mine right between the two. I use 68 BB towers. Adequate clearance for the fan and radiator. HEI distributor has adequate room.
The truck was a tall hump (I6 and granny 4 speed) and the Tremec fits just fine.
Made my own transmission cross brace, custom drive shaft. I run headers and a hydraulic clutch. I would recommend Chevelle headers as all truck headers hang too low for a lowered ride.