Installing headers -- While engine pulled or after re-installed?

Like others have said, if you're going to the expense to buy headers...get long tube ones. One thing that hasn't been mentioned, is since you have some good, big ol torsion bars and will have to use the BFH to make a little room, you might be better served to buy the headers raw steel and then get them coated after you beat em up a little. TTI headers for 67 & up A bodies should have one slip tube on the drivers side, so that will make them easier to get in and out with the motor in place. That will help if you have to take them in and out multiple times do the dinging. I think the passenger side will go in and out pretty easy. Hopefully, someone will tell you if you need a 90 degree oil filter adapter in an A body with TTI headers, which is something else to consider. If you do end up buying raw steel headers, Calico Coatings near Hickory, NC is a great place to get them coated after you make them fit. Good luck with it! :)