I have read the novels for Yokozawa and read and re-read Sekaiichi Hatsukoi and I cannot see that the author has given them positions. So based on personality type I am going to go with Takano seme and Yokozawa uke. Takano always instigates with Ritsu and can be very forceful (knows what he wants and is going to get it) and I haven't noticed him suggesting a swap lol. Yokozawa has a very caring almost motherly personality outside of work and was in love with Takano so knowing the drunken tryst they mention I can only think it went the way I mentioned. Also he is currently the uke with Kirishima and Kirishima acts in the similar way to Takano in that he always up for and instigates the sex :)
Anyone who read the whole series could you please tell me Saga was top or bottom in the relationship with Yokosawa?