Advice to gain girth mid shaft/base?

[alwaystrying]

I am not that thick but I noticed I am the thickest just under my head? This is not the norm is it? The tip to mid is about 5.25" around, whereas toward my base I am 5 even or so. I am currently trying to hammer away at lengthening, and was told that lengthening (especially at low angles, pointing down) could give a little base thickness....any thoughts as to a little here and there to try and even myself out girth-wise? Would clamping the base off or where I am thinnest help? Do you gain thickness at the site of where you clamp? Thanks.