Hexidecimal list <- Use this link to view all the Kanto Pokemon and their associated Hexidecimal values. You can force an encounter with ANY Kanto Pokemon in RBY on that list provided you have a Pokemon with a Special value corresponding to it. For those Pokemon at the top of the list, you can add 255 to their value(since the list repeats post 255, hence 256 would be Rhydon). To ensure you meet the Pokemon you want, you simply encounter a Wild Ditto and have it transform into the Pokemon with the Special stat wanted(since the encounter uses the special stat of the Pokemon last fought/encountered and Ditto copies the values when transforming(only thing it retains is hitpoints)). Meaning its possible in Red, Blue or Yellow to get Pokemon not native to your game without having to trade for it. You can even use the Ditto Glitch to get Pokemon that are hard to acquire(like the Kanto starters or Safari Zone Pokemon since Pokemon encounters via the glitch do not flee).
A special case of the above glitch can be found on the way to Bill's place north of Cerulean. To perform it, you need an Abra(which you can catch south of Cerulean). There's a trainer with a level 17 Slowpoke who has a Special stat of 21(the same as Mew). You then simply glitch a Trainer(say the one to the left of Nugget Bridge) by Teleporting back to Cerulean at the same time you come into his view. Then battle that Slowpoke Trainer(be sure to make him walk to you) and defeat him. Teleport back to Town once you do and walk towards Nugget Bridge. Menu will then open(which is a good thing) and then close to start an encounter with a level 7 Pokemon(in this case Mew). If you use "Growl" on the Slowpoke(or any Ditto you encounter for the Ditto Glitch), you can reduce the level of the encounter Pokemon by 1 for each time you use Growl. If you do it 6 times, it will be level 1(wherein you can pop it to level 100. Just know that Mew only knows Pound so have TM/HM's ready).
I also never have two Fire types within my party at any one time. If I opt to utilize Vulpix/Ninetales, Charizard or w/e Fire Type I have with me gets boxed. In Yellow version though, Charizard's usefulness is far greater due to being able to learn Fly. Therefore I can forego having a Flying Type like Fearow or Dodrio for getting around the region and lessens the need for Psychic Types since I can use Charizard to fight Grass, Bug and Fighting Types(while Sandslash or another Ground type can handle Poison and Ghost(since they have Poison Typing and no Levitate ability)). Also, if you want a solid Normal type to use, Tauros is widely considered to be the best option due to its incredible power and speed.
*I should add that the Ditto Glitch can be used to duplicate items(Ex: Master Balls or Rare Candies) using Hexidecimal values of 182 to 184(which are stable). Simply defeat the encounter Pokemon rather than catching it. Upon encountering them, items in the 6th slot will be "duplicated" This method is stable and I haven't witnessed it corrupting the game unlike the "Old Man" method in Red/Blue.
