I used the AE VAG 375 guides for exhaust as they were shorter than the Tranco G1525 or G211. I tapered the square VAG guides before insertion. Note that the tops of used valve stems usually need the burr created by the rocker to be filed off before removal from an old guide and usually also to be done again to make it run smoothly through a narrower new guide! I used to have a valve guide removal and insertion tool which was really a stepped punch, but I could not find it! So the slight burr caused by the force of inserting was reamed away.
I measured the height the original guides protruding above the head face without the bottom cup installed. This was 16mm. I then measured the thickness of the head into the port. This was 36 mm for inlet and 26 mm for exhaust. This was the length of the original guides that had been flowed into the ports. I do not know if the protrusing was correct. One would need to see how much more they could come up before hitting the collets when fully open to give maximum support to the valve stem, but there was a groove in the original guides that lined up with the top of the installed bottom valve spring cup. I also found that one pair of cups needed pressing together to seat properly indicating that the pair of valve guide holes were not the same distance apart! Jowett engineering?
All components were washed in the parts washer before assembly.
The heads were fitted using some original Halls steel/asbestos/copper Jupiter gaskets. I use hylomar on the liner seal and Loctite si 5660 on the water seal covering all 4 faces (block, gasket, head) with a thin coating on each head. All faces were previously scraped, lightly wire brushed and cleaned with meths. New gaskets were fitted to the carbs with the halite one next to the carb and the paper between head and spacer. All nuts were secured with threadlock.
Care was taken to seal around all head bolts both top and bottom with si5660. New square rubber ring was fitted around centre bolt but some si5660 was also used. I previously had used solder under the head nut washers but now use si5660.
It took many attempts to get a consistent correct result. We had difficulty fitting the dowel locator, eventually reaming out the holes in both sprocket and cam shaft, and finding a dowel that would fit. The original dowel was distrorted and another from a spare shaft was a slightly different size. A few attempts were needed to correctly take up the slack in the timing chain. Once three consistent checks were done using the feeler gauge method, the setting was cross checked with the dial gauge. Note it is very important to set the tappets to zero gap on No1 Inlet when no 2 inlet is fully open. It was also important to somehow find a way to keep the dial gauge on the spherical top of the rocker arm and on the axis of the push rod. This was not a quick or easy job! However, the net result is confirmation that the feller gauge method is easier and more reliable than the dial indicator method. Perhaps not everyone has a 21 thou feeler gauge but sets in increment of thou are available.
Donal asked on Facebook about what is in a head gasket kit.