Great shot Scott! Bit of variation in ephemerides for Lovejoy, John, depending where you look. These are some estimates (full ephemerides if you follow links):
http://cfa-www.harvard.edu/iau/Ephemerides/Comets/2007E2_1.html :
2007 04 17 8.6
2007 04 18 8.5
2007 04 19 8.5
2007 04 20 8.5
2007 04 21 8.5
2007 04 22 8.5
2007 04 23 8.5
2007 04 24 8.5
2007 04 25 8.5
2007 04 26 8.5
2007 04 27 8.5
2007 04 28 8.6
http://www9.ocn.ne.jp/~comet/eph/2007e2.html :
2007/04/17 7.6
2007/04/18 7.5
2007/04/19 7.5
2007/04/20 7.5
2007/04/21 7.5
http://www.ast.cam.ac.uk/~jds/07e2.uk :
April:
16/17 7.6
17/18 7.5
18/19 7.5
19/20 7.5
20/21 7.5
21/22 7.4
22/23 7.4
23/24 7.5
24/25 7.5
25/26 7.5
26/27 7.5
27/28 7.6
Also chart below.
Cheers -