Welcome!! I am also new here. I only have experience with S. Ater
formerly S. Obesus, however this usually works for anything short of my very territorial Rhino Iguana!! LOL.
We all know that Chucks like it hot, very hot. This can make them or any other herp very excited when a keeper approaches them. They are in a sense ready to go into defensive mode... Hide, bite, simply get away. Reptiles are not affectionate, but can become tolerant. They are not trustworthy, nor are they friendly. Again, they can become tolerant. Try spending some time handling your pet shortly after he wakes up, and before he warms too much. Also try coaxing him to crawl onto your hand and feeding him with the other. Always approach a lizard low and from the side and rear. This will give you a sense of it's frame of mind very quickly. If a hiss, and whip of the tail occurs don't pull back quickly, try to rest your hand near him and gently inch your way over. Sneaky and subtle are your friends here. Reptiles are very sneaky, and territorial.
Once you have made basking buddies, which I think is the hardest part, try sliding your hand underneath and position your index finger and middle finger on either side of the neck. I have found that Chucks are not very flexible and have a rather difficult time turning to bite when being held in this manner. They also seem to have a bit of a blind spot below and just rear of the eye... It is probably the lymph sacs!!
Once you have him move slow, and just try some simple petting on the neck and see if this makes him nervous. Also try this with the tail. Once settled down try switching hands a few times.
You may find that you will never be able to just reach in and pick him up. I have had probably 20-25 Chucks and out of those maybe two that were ever very tolerant of me.
I just recently captured an adult male that was skin and bones, and could barely move... Our deserts are extremely dry this year.
He didn't have enough strength to inflate himself and become stuck. This made me quite sad. I caught this guy in April and he immediately took food from my fingers. I have been working with him every day and he is by far the healthiest Chuck I've ever seen...(Now, that is). He has gained all of his weight back plus a bit, and has become quite tolerant of me. He may be a special case, but my approach with him is also my advice to you.
Go slow, be patient, and take your time. Chucks live a long time and are creatures of habit. If they get used to a hand basking with them, they will certainly get used to basking on that hand, then going for frequent trips outside of the cage on a magic flying rock... (Your hand).
I hope this helps, and I'm sure that others here will have tips for you as well.
P.S. I've heard that Angel Island Chucks.. S. Hispidus are usually very mellow, and friendly... I mean tolerant. I'm currently looking at buying a few. I'll let you know how their disposition is.
