I want to point out that you are going through a lot of effort in order to install a knock-off cylinder head onto a 1.6TD block. Although I believe it is doable, it is both risky and the end result is questionable (low compression, poor combustion, hard starts). I don't think you ever replied about whether or not you actually measured the cracks between valves and compared that to what Bentley says is acceptable. Is this still going into a Vanagon? In Montana? In that situation, I would pursue the MF head further before opting for the aftermarket AAZ head. If the MF head was indeed unusable I would see if I could find a usable OEM solid lifter head. Failing that I would opt for an aftermarket solid lifter 1.6 head. I would not opt for the aftermarket AAZ head until those prior options were exhausted.