Has the price of Aluminum gone up that much??? then again, that was 10 years ago so I guess it's been a long time. My last one was $850 which included Epoxy coat and 1/2" fittings with 4 baffles.
Don't tell the CG you're foaming it in, they don't allow it anymore... But I wouldn't do it any other way cause crap moves around way too much even if it's bolted in there really good.
Evercoat makes the two part foam called foam-it.... Use is sparingly... dump some in and let it rise before you start dumping more.. Otherwise you're tank will pop out.... Don't laugh, it really does!! We had a guy at the marina who got a little over zealous with the foam and when we got back from lunch the tank was 6 inches out of the hole! lol
Don't put anything rigid under the tank to raise it up. Have the tank company weld 4 tangs on the top of the tank that you can raise it up and put a screw in the stringers.