Yeah, I have a '78 3001 & I love it. It's my fave of the three Ricks that I own (4001, 4003). I've had it since '94 & have recorded & gigged extensively with it. In my experience it has more fundamental lows than the 4001/4003 & just a great pissed off P-bass type of tone. Bolt on neck & yes, VERY heavy. Certainly not as elegant as the 4000 series, but just a fantastic bass. They're really the biggest sleeper Ricks out there.
I'm not a slapper, but I think this bass lends itself to that approach better than the 4001/4003.
John Hall (RIC CEO) is quite fond of these basses & drops some fascinating factoids on the Rick Forum from time to time. Like this one:
"The creation of this series was overseen by our chief electronics engineer at the time, George Cole. (He was also the architect of the TR amp series.) He is also a superb bass player and worked with many of the greats in the past. As such there were a number of little "quirks" or optimizations he proposed and/or introduced on these instruments. The pickup design is utterly elegant, with a single coil fitted around a bar magnet that rests against the steel frame, that then become two poles pieces at each our edge of the pickup. The design not only shields the coil very well, it has a pseudo-humbucking effect that doesn't change the single coil sound.
Some other features are the lead weights under the fingerboard to put extra mass precisely where needed to even out the notes across the fingerboard. (That technique was expanded to the 4000 series for awhile too.)"
Obviously if the original pick-up is gone, so is some of it's inherent magic. But Ric5 makes a good point....a HB-1 would be an easy & interesting mod.
Good luck to you sir.