I have this idea in which Colt hates Simon, but they had to make a temporary alliance against Tom Ryder.
This in a universe in which the astrophage doesn't exist, the events of The Fall Guy doesn't happen and Simon lives in the same time and universe than the Coltland; Grace is a middle school teacher, Colt is a stuntman and Simon is a underwater welder who takes security related part-time jobs (he is still a convict).
Grace may be too oblivious to notice how he has a talent to attract the wrong kind of people, but Colt is not that innocent. He can see the eyes that the convict ("really, Ry, from all the friends you can do you decide to go for the convict?") makes to his brother, and he was doing all what he could to stop his advances even before they reached Ryland. However, when he saw Tom Ryder (Tom freaking Ryder!) make the same eyes to Ryland, Colt found himself in that hard situation of choosing sides and between Tom Ryder, and the convict, he is choosing the convict.
Colt thinking that the only way to stop Tom Ryder is finding Ryland a boyfriend first, and realizing that his only option is Simon.
Simon don't wanting Colt's help until he sees Tom Ryder uses his charismatics powers to chat with Grace and make him laughs, while he can hardly say hi to him without stuttering, and realizing that he actually needs all the help he can get.
Colt teaching, much to his disgrace, Simon how to flirt and have rizz.
Simon, much to his disgrace, having to write down Colt's tips in a notepad, because Colts gives to many information for him to retain it by himself.
Colt realizing that Simon is so socially awkward that he didn't have to stop his advances through Ryland in the past, because Simon wouldn't have got anywhere by himself.
Very awkward practice sessions, because Colt looks like his twin and everytime that Simon wants to practice a confession or a line, his mind tricks him and make him think that is really Grace, so he panics each time.
Colt making everything that is possible to stop Ryder and give time to his champion (Simon) to score some "points" with Ryland.
Colt having nausea about all this because, he is going against all his principles.
Tom Ryder knowing what Colt and Simon plan is and mocking in front of them everytime that they miss an opportunity and/or he wins a "point".
Tom Ryder ready to confess making Colt and Simon to panic and having to rush.
Simon forgetting everything Colt taught him when he is front of Grace and going without filter:
Simon: "I want to invite you a coffee, because I like you, and I want you to notice me, so you can like me back, so I can ask you to date me."
Colt, who is watching everything, hiding his face in his hands as he screams: "Aaaargh."
Grace: "I would love to get that coffee and to notice you and to like you back, so you can ask me to date you."
Tom Ryder, who was also hiding beside Colt and laughing at everything until this moment : "What?!"
Colt, who will take what he can: "Unconventional, but if it works, it works."
Grace, smiling: "What are we waiting for?"
Then Grace takes Simon hand, who is smiling very happy and confuse while they go in their way to have that coffee.