273 to 360 swap. same converter?

yes he got lucky. all torq convertors that I can thin of have a registor that fits very snug. If you want to use that trans, the B&m flexplate and the spacer ring would work. You may want to say a prayer to the trans before you drive it each time though as the extra torque of the 360 may put the hurt to that tranny in short order. Especially if is bone stock.