With the rear tub and hard top sides installed, I thought I'd try a test fit of the doors before installing the roof.
Oh dear. They didn't fit. There was insufficient room at the top - in other words the bulkhead was obviously not correctly aligned, as the top of the bulkhead was leaning towards the rear of the vehicle.
I loosened the three bolts holding the passenger wing to the chassis, and did the same for the drivers' side. I also loosened the steering column lower clamp bolt, so that the collapsible column was free to move slightly. Then I inserted a Quick-Grip clamp on each side (in spreader mode) between the hard top door frame and the top of the bulkhead. I then measured the gaps.
The top of the driver's door (the bit where you would rest your arm if the window was removed) was 863mm.
The bottom sill measured 880mm.
For the passenger side, the door top measured 857mm.
The bottom sill measured 875mm.
Alternatively tightening (or in other words expanding) the clamps and measuring, I finally got the measurements fairly equal:
Driver door top 877mm
Passenger door top 877mm
I re-tightened the six lower wing bolts (three on each side) and the lower steering column clamp bolt, noting that the collapsible bit had moved by about 3mm inside the ribbed section. I then released the clamps and just for luck, re-measured the gaps.
Drivers door top 875mm; bottom 881mm.
Passenger top 872mm; bottom 877mm.
That will do nicely; the doors would now fit!
Ah yes, but the fun wasn't quite over. Having carefully installed the captive nuts in the four holes on each side of the bulkhead for the door hinges, I found that as soon as I tried to offer the fully-assembled door up to the bulkhead, the captive nuts fell out. Rinse and repeat.
A telescopic magnet proved extremely useful in fishing out these captive nuts from the bottom of the bulkhead frame, but after the third unsuccessful attempt at door installation I started getting tired of this.
I therefore removed the door top in order to decrease the weight. Then I removed the hinges from the door and installed them loosely to the bulkhead first. (This time I was able to hold the captive nut in place with a small screwdriver whilst inserting the bolt through the hinge).
I then attached the door to the hinges, and once again used the Quick-Grip clamp to ensure the door was straight and level before tightening the hinges, installing the door stays, and then refitting the door tops.
You need good quality Quick-Grip clamps which have a decent steel bar for this sort of job. Cheaper ones would just bend.