I have adopted a 15 year old neutered male, Russian blue tuxedo cat. He is as tall as Abe Lincoln! Seriously! 36 inches from tip of nose to tip of tail.
Kept he and Keli separated for four days, letting them sleep on each other's blankets and changing them around. Letting him into her room while she went into his.
The first time they met, she had gone outside for her daily 15 ft constitutional, and had come back to the screen door where he had been waiting to meet her. They went nose to nose while I sweet talked to them. and eye balled each other and then both turned away peacefully.
A couple times he, Jeffrey, has been up on the bed with me, when she has arrived. She has taken to sitting up on top of the bookcase headboard and looking down upon us while laying on my favorite sweater. Oh the sacrifices I make for her.