Sorry folks but I got a bit panicky and couldn't finish the earlier post.
Dave, returning to your RT thread:
Before you put any paint on the model, and just in case you were unaware of the issue, you might like to file off all but two of the moulded external roof ribs?
RT roofs (in between the front and rear domes) were made of wood. Laminated rather like the DeHavilland Mosquito or those classic motor torpedo boats! Unlike them however, the RT had thin alloy skin sheets over the top that were butted, bedded in sealer and screwed at the joints.
In the early days the joints failed and leaked badly, so LT resorted to sticking temporary tape over them until a more durable sealant could be found and applied! It was only in the last few years of RT operation that the problem resurfaced and some vehicles had one or more aluminium bands screwed on wherever required as a local repair job.
Below is part of a photo (taken in 1975 I think?) of a roof in near original condition. It correctly shows the raised mouldings only at the fore and aft joints with the metal domes:
There appears to have been a problem with the offside grab pole fittings though? Four little patches have rather prominently appeared on this one!
Hope this helps?
Pete.