Okay, I found the reference I was looking for....here are the relevant sources:
1) Jub. 4:30; Justin, Dial. 81; Irenaeus, Adv. Haer. 5.23.2; Midr. Ps. 25:8; Gen. Rab. 19:8, 22:1; Num. Rab. 5:4; Pirqe R. El. 18. (Psalm 90:4 as key to exegesis of Genesis 2:17 and 5:5, such that Adam's 930 years fit within a single 1,000-year "day")
2) Rev. 20:4; Justin, Dial. 81; b. Sanh. 99a; Midr. Ps. 90:17; Pesiq. R. 1:7 (Psalm 90:4 as key to messianic exegesis of Psalm 90:15; Isa. 65:22, etc., such that the "day" or "days" of the Messiah equal a thousand or several thousands of years)
3) Barn. 15:4; Irenaeus, Adv. Haer. 5.28.3; b. Sanh. 97a; cf. 2 Pet. 3:8-10, Pirqe R. El. 28 (Psalm 90:4 as key to messianic analogy of Genesis 1 creative days, such that six "days" of 1,000 years each are followed by a millennial "Sabbath")