Compass Swings.
BEAgle,
There speaks the voice of experience ! (we can only sympathise). Was the E2b really so important that they had to cook the operator ? IIRC, it only had 5 deg. markings, I had a stick-on thing on the screen of my car in the early '60s which was much the same (and about as accurate!). And if the hood frame was the cause of the bother, didn't it worry the main compass as much as the E2b ? (speaking as one who vaguely recalls the Gyro Fluxgate, but nothing later !)
Our Vengeances got two twirls only, and had to count themselves lucky with that (which may have been a factor in our Flight getting good and lost on our way to war, in circumstances where a cub scout would have had no trouble in finding the way).
Now your small turntable with a locked main wheel on it: that's so obviously the answer, it would have to be big enough to take the whole outside bogey of the big boys (can you lock a single bogey ?). The tug and push-pull dolly would have to be "de-gaussed", but if you can do it with a 20,000 ton liner, a tug should be easy.
(Very Sad Story of WW2: our ship arrives in port and parks. Sighs of relief all round..... we're home and dry now..... switch off de-gaussing cables..... there was a magnetic mine sitting right under the keel !)
Danny42C