Deciding on replacement intake (318, details in post)
Looks like I may have caught head gasket failure over cylinder 7, also the coolant was more water than coolant in the system, fuel in the oil (gulp) and the oil hadn’t been changed in a long time.
I've never owned an American vehicle that hadn’t suffered some sort of neglect under British ownership (don’t know why, they’re not really any different to maintain than anything else) and I’ve had around twenty over the years. I generally assume that bad things have happened whenever I buy one.