By the base of the spa do you mean the cabinet or the ABS substructure? If the base of the spa is the cabinet, then I'm OK.
The tub will be surrounded on 4 sides. From back to front, I'm constrained to the 87.5" length. From side to side I can make a cut and remove a board and get 90". Given that information, do you think they'll be able to fit it in? Should I let them know they may need a crane, or will a few lifting straps work OK?
Unfortunately the deck was built 7 years ago - before we had aching joints and decided on a spa. The way the deck is built, making the back-to-front measurement any larger would have meant a total structural overhaul -- new posts, stringers, headers, etc. It would have been easier to build a new deck. Not in the budget after buying such a nice spa. :-)
We're very excited for the tub! We did lots of research and liked a few spas, but the Vanguard was the one that was right for the two of us, and that was even more clear after a few wet tests.
Thanks very much for your info.