[Moma]

Approach a different group of lizards i.e Asian lizards. However, lizards tend to be understanding and 5 inches doesn't sound bad at all. You might have to get your tongue game real tight (I am talking cunnilingus) to compensate if you suspect snickering from the reptiles. A lizard will concede with the slam if you make her toes curl with the tongue game.

I would suggest approaching shy lizards. Your size isn't as intimidating so you will actually be better received. I find that short guys get a lot of ass because lizards underestimate them.
Perhaps you may want to look into also approaching Asian lizards. From my knowledge, they are built for smaller guys so you should fit right in.

Try jelquing and stretching your joint. There is an existing thread on this (forum search). You might be able to add an inch to your girth and an inch to your length. Lizards gasp louder from a fat one than a long one.

Go forth and do diligence.