Hi Doug - Yeah, good question.
I removed the foot & out fell ... a perfectly intact coupler ... with the splines from the sheared-off upper driveshaft still stuck in it.
And we're up on an expensive slipway in the Solomon Islands...
Luckily, Solomons respects "In Transit for Foreign Yacht" so we didn't have to pay duty, & the DHL woman in Honiara is wonderful & forwarded the
parts to us. Got the shaft & 6 related bearings from CLLS in
Singapore in just a few days (& for cheaper than I was expecting).
Taking the top off the SD31 & the upper (reverse) gear comes off with it, & the vertical driveshaft just lifts out! Replaced all the bearings, dropped in the new shaft, put it all back together, & voila! I also replaced the shifter, as it's
bronze & the other side had worn badly (causing reverse to slip sometimes).
A side note, that probably works on your Volvo drives as well. In taking the foot off, I found 3(!) plastic bags in the cavity at the joint. They'd been sucked up from the bottom of the foot & gotten stuck. On port side I found 2 more bags, extracted with one of those grabbers used to retrieve
lost bolts from under engines. So I drilled 4 small holes around the
water inlet at the bottom of the foot & threaded some seizing-wire through them. This should keep out any more bags when motoring in badly polluted waters (parts of Indo can be terrible). I'll be putting this idea on our
Sail-Drives page to go with our other recommended sail-drive modifications.