The LT5 does use a bit of oil that way. Several have fashioned an oil catch can to collect the oil before routing the vapor back to the plenum. You can see such an arrangement in this photo of =Jeff='s LT5.
A local speed shop (Winner's Circle) has an assortment of cans in various shapes. I'll be checking that out as part of a winter project.
I'll keep y'all posted.
P.