Squeeze, that's all good news! That tells me it should be totally possible to put a tank within the frame, forward of the rear axle in a 64-66 GMC short-bed 1/2-ton truck.
When I have a truck, or better yet, before I buy (so I know what I'm getting into), I can check the documentation and get the specifics. If I can't buy a reproduction panel tank, I'm sure I could have one fabricated, or like I had been thinking, maybe an S10 tank would fit. Either way, something would work, and it would be much safer than the rear-mounted tanks and I believe much safer than the in-cab tanks.
Thank you so much for your advice. I'm really excited to try it. Whenever I do reach that point, I'll take photos and post them on this forum.
