Do they have the straight hex shafts with couplers and no u-joints like a 944? If so, the bearing holder next to the sproket should have slots where the bolts hold it onto the head and you can adjust it that way. Needs to be very close to lined up or the hex shaft will wear in no time.
It sounds like you have a non-tracker head. You will need to switch it over to the pto type shaft to drive it. You do not need to add any of the senors and then you can tilt the head manually. If you use the old hex shaft it will not work very well and I don't think that you will be able to tilt the head at all.
I don't know when they went to the pto style, but I'm pretty sure a 2188 and 1083 should have the hex shafts. What you might need if you have a field tracker and want to use it are the flexible shafts that work like a pto shaft going to a tractor. They just have the hex female end to mate with your combine's hex shaft. When I modified our 1083 to line up with our 1688 we didn't want to spend the money on the kit, so I can't use my field tracker, but I don't really need it on our terrain.