I use 80/90 in front, 85-140 rear. Good to go. Use a good quality RTV as a sealer, get the surfaces cleaned well with a scotchbrite pad & brake cleaner, wiped down with a lint free cloth. 1/4" bead of RTV, carefully mate & torque the cover bolts in a criss cross pattern to 30ft lbs. Wait about half a day, overnight is better, for the RTV to cure. Then fill, 2.7 pts in front (1.35 qts), 4.7 pts rear (2.35 qts.). If you don't have aftermarket covers with an elevated fill plug you'll have to get the last bit of oil in through the breather port on the housing. Don't just fill 'til it runs out the hole, you'll be short some oil.