West coast rapper E-40 will release two solo albums next month that will feature a guest appearance by Tech N9ne. HipHopDX.com highlighted Tech N9ne and Bun B as two of the artists featured on the projects. E-40 will release the albums, Revenue Retrievin’ Graveyard Shift and Revenue Retrievin’ Overtime Shift, on March 29. The two discs will add to E-40′s Revenue Retrievin’ series. Click here to read more about the Revenue Retrievin’ series on HipHopDX. E-40 will join Krizz Kaliko and Bun B at the Paid Dues Festival in April.