If he was wet before you lifted him id try it earlier, double sheet the bed, just in case, so you can whip one set off but be left with a dry one...and reward him in the morning for his efforts, say nearly there good boy for trying.
Oh and tell him , you must wake up for a wee wee when you need one.
I lift right to loo and plonk, they were often still asleep but id say wee wee and they would!