My tank on my 68' was in bad shape, I got the new fiberglass one from Inland RV. I love it. Will never have a problem. and it had a flange around the top that I drilled holes in and screwed it to the floor for extra support.
May you have at least one sunny day, and a soft chair to sit in..
2008 5.7 L V8 Sequoia
AIR # 31243
WBCCI # 6987
FOUR CORNERS UNIT