When it meant a lot of work to make Ho the engine mounts I sort of quit while I was behind

If you look at the bare block you will see that there are virtually no points along its length to stick any mounts on either side do you are left with tieing into either end or using the intermediate cross shaft mount or the actual exhaust mounts or the from end somewhere

The front of the engine has 2 knock sensors screwed to it as well so if you turn it through 90 degrees and make it onto the drivers side you've got to think about where the rack is going to go as well as the sump sits very low and the bowl is not just at the front but at the back as well as the whole thing is designed to be slotted in from underneath

Not an issue on a front wheel drive car but a right pain in the arse for turning it sideways

That said, there are plenty of Volvo peeps who will have done a rwd conversion so maybe scouting about on their forums would be an idea