Sounds like a 10 - 15 gallon tank. You could probably house 3 - 4 small lizards in it max.
The basking temperature sounds fine, just make sure that the cool side is in the 70s or low 80s. Put in a deep substrate that they can burrow into and some logs or rocks they can climb and hide under.
If you want multiple lizards / species in a tank that size it might be better to go with a smaller species of Sceloporus.
At the office I set up a 10 gallon tank and it comfortably houses 1 male and 2 female sagebrush lizards (Sceloporus graciosus)and 1 female Slevin's bunch grass lizard. The three sagebrushes who were supposed to be the sole occupants get along great and are out all morning and into the mid afternoon, but around 3 they usually bury themselves. The Slevin's came home with one of my co-workers after a trip to Arizona and was added to the tank. She hates everyone. So she comes out at 3 after the sagebrushes are in bed, that way she has the tank to herself.
I think with a tank that size you could house:
1 male, 1 female western fence lizards
or
1 male, 2 female sagebrush lizards
or
maybe a pair of sagebrush lizards and a pair of side blotch lizards.
Alligator lizards and skinks like it a bit cooler and moister than the Sceloporus, so unless your tank was at least double the size you indicated the odds are no one would be very happy if you tried to mix these guys with the Sceloporus.
Good luck,
Alice