The Overdrive I'm using came from a 1969 Alpine GT coupe (Barracuda wannabe). The gearbox and OD are, I believe, identical to the S V all synchro box. As far as I know It's a D-type overdrive. The input shaft was too long, and bell housing was different. The gear ratios were also different. I changed to a 10-spline S V input shaft, and swapped all the gears from a S V transmission into the GT gearbox. I replaced the GT gears on the OD mainshaft with the S V set, and used the S V layshaft as well. It worked great, but made some noise from the start. It recently gave out, and I'm running it in direct.
I recently talked to our local Volvo guy who told me D type overdrives were fitted to Volvos thru 1966. He also claimed that a J type OD would bolt right up to the earlier D type Volvo transmissions. I can't confirm this.
Sorry about the false alarm.
Rex Funk