I apologize to @mmarcovitch for a brief digression, but I want to reply to @Saul 's comment. Firstly, there must be some published accurate dimensions of the M1 Abrams tank (which is Saul’s chosen subject). Use those known dimensions with photographic coverage to estimate other dimensions. Such estimates are of course not as good as direct measurement, but they might be your best option. I have estimated many many thousands of dimensions for my subject in this manner. Even though I have about 1500 direct measurements of various features (see below), it is never enough. I have personally captured about 3500 high-resolution photographs of my subject to use in making such estimations. The dimensions and photographs that I have spent considerable effort to acquire are published for free on the web, by the way. (There are rare exceptions; the owners of some artifacts asked that I not publish my research from their material.)
Here is a video I created 8 years ago describing the process I use:
Secondly, I don’t consider having dimensions of my chosen subject to be luxury. I have spent thousands of dollars traveling across country, purchasing precision measuring tools, and arranging time with museums etc. to acquire my own measurements of my chosen subject. I suppose you could say that I have the luxury of being in a financial position to invest that money (and time) into research on what for me is a serious hobby. For what it’s worth, here is an example that I used to capture and record some dimensions of one of my subject’s components (the numbers in red circles are generally inch dimensions):
