Depending on the particular HB-1 you could end up with a brighter bridge pickup after doing this. At least if the p'ups in my S-100s are representative of the '70s norm and my T-bird's p'ups are typical of current manufacture. Compared to the HB-1s in my S-100s, at same amp settings (Vox Pacemaker & newer AC-4, Fender Princeton, Hi-Tone 50) the LB-1s are darker. Not by much but enough to make me turn the amps' treble pots up a hair to compensate. The HB-1s do have more midrange oomph, though, if that's your main goal.
I wouldn't sell the LB-1 bridge pickup short. The one in my T-bird has more cut-through power than I'd expected. Works excellently with mid-rich amps like the Voxes and big(ger) bass OD pedals like the Visual Sound Open Road.
-Dave-