Lifting Tub for Repair

Making a last-ditch to effort to save the tub I put 2 new pumps and a heater in this year (plus a new cover). I can see a big leak but it's unreachable; it could be as simple as a loose clamp but even the longest arms can't reach it, much less get tools there. Tried JB Weld (wet) but it didn't work (probably too cold out to cure properly). Can't turn the tub on its side because the pumps were never attached to the base properly. Thinking about getting a jack under it and gradually lifting each side until we can get a cinderblock under each corner. I don't really know much about tub construction other than what I can see. Would it be safe to work under the tub like this? Does anyone have a better idea? (It's a 2010 Clearwater St. Andrews if that means anything to anyone.)