Stargazer.

First, I've been using the AMT kit, which, after converting 141.72 m to inches, and dividing by the 10.5" width of the kit's primary hull, comes out to a 1/531.38834.  Drawings (1/2000 scale) for Constellation class Star Cruiser, can be found in Jackill's Star Fleet Reference Manual Ships of the Fleet volume II. The primary hull is deeper, and larger in diameter than the Enterprise. These dimensions are quoted from Jackill's.

  Enterprise: Primary hull length; 146.31 m width; 141.72 m height; 32.94 m 

  Stargazer: Primary hull length; 205.18 m width; 161.88 m height; 50.91 m

The extra width, 20.16 m, is an extension of the primary hull, an added ring outboard. the extra height will require adding material between the upper, and lower hull halves, 17.97 m more. 

Hello Cosmic wanderer,

 There is alot of work ahead if you are starting with the two kits. I just finished a Stargazer master pattern for a client.

First, make sure you have research on the filming model, that is you final guide. You will need an engine mounting cross bar, top and bottom. The dorsals will have to be modified. The engines will need their tails 'bobbed'. An entire mid saucer section will need to be created for the two kit upper saucers to mate to. A new bridge, new lower sensor dome, two impulse drives, from the kit. Lots of detail goes on the new saucer mid section, the cross bars, windows and cargo doors on the saucer. I think you get the idea! It will be worth the effort if you carry it through to finish. Best of luck!

Regards,

 Scott 

Thank you folks, I've got a few pictures thats all but its a long term thing now I've other things on my mind at the moment.

edit.

I've been thinking two what if builds, I've an idea how the saucer sections should look and the new hull but not sure about how to mount the engines.

When I've a better idea I'll let you know two interesting somethings, from two somethings that bring back bad memories.