Do these install easily on this bass or will I need to do some routing?
The S-Tek is a monorail while the BA II is not. So my guess is you'll have to do something.
S-Teks are great bridges (save for the intonation adjusting problem, which never bothered me) so I don't get why you'd wanna change it, lots of bridge to body contact. Plus, BA's are meant as Fender replacements, replacements for those lame assed low mass bridges I hate so much.