Let Me Know if You Have Allison Transmission Fluid Questions

Tom, welcome to the forum. Your info is very valuable to all of us. I have a 97 HR Imperial with a 3000 series Allison. I tried to check the fluid level using my touch pad but I guess I don't have that option. Is there a way to upgrade my touch pad for fluid level? Also, does it hurt to continue running Dexron lll or would it be better in the longrun to change over to synthetic? I recently purchased the motorhome and it looks like service's have all been done with Dexron. Thanks again for the help!
Steve