AJ6/16 to 265/290 questions

I am usually on the Saloons forum but I have a AJ6/16 related question.
I posted this on the XKS forum but thought it may be a good idea to put it up here as well. If anyone can help I would be grateful!
I have a 265 bellhousing, flywheel & adapter plate.
From what I can tell, the adapter plate (what would be a flat steel plate on an XK engine, but is instead about 2.5" thick cast aluminum) will fit any AJ6 or AJ16 engine, is this correct?
I am wanting to mate the adapter plate to a Getrag 290 transmission, do the 265 & the 290 use the same adapter plate?
Lastly, I have the 265 stock flywheel (seems a good compromise between the heavy dual mass unit and the light aluminum unit). Will this work with the 265 adapter plate 290 transmission combination?
Thanks in advance!