Ace,
I've redrawn the launchers and these should now match the heights (in pink) you gave. Also the bases were a bit off so I've redone them. It's surprising how many differences there are between the launchers on the T82 and T42, even the launch rails were a different shape (which I hadn't noticed before).
If everyone is happy with these, and your happy with the below decks parts then I'll marry the two up onto the sheet.
As a general rule, I'd suggest kitbashers only use the launcher from the Type 42, as the one on Bristol seems only to be specific to that ship, even CVA-01's launcher was of the variety fitted to Type 42.