I would force carbonate instead of priming your keg. You have more control. A Scottish ale should have .75-1.3 volumes of CO2 (they're pretty low on the CO2 in general). At 68°, pressurize your kegs @ approx 4.4 psi. Purge your kegs 2-3 times to remove O2 from head space. Rock your kegs until you can't hear any gas going into them. Disconnect and store. I usually refrigerate to get gas to dissolve quickly into beer so I can drink it, but w/ a Scottish ale, let condition at cellar temp for a few weeks at least. Give it a try. Start conservatively. You can always add more CO2.