WoW! I used to use such a system a time warp ago . Except we had 2 bass bins per side and supertweaters above the hi horns (where is the face palm emoticon).
ASSuming that it is still working - it is BIG, HEAVEY, and plays pretty loud with not too much watts input. I would be very cautious about the condition of the drivers. That system has to be crossed over correctly and compared to modern systems uses a lot less power.
FH2s - it is very easy to destroy the dual 15s in the FH2 bass horn by trying to get more lows out of them than that box can produce. That horn unloads around 50-60hz. Even in perfect condition you WILL NOT get any useful output below 60hz. It also has a strong rising response up to 200 - 250hz needing some heavy eq. Finding replacement 15s for that cab may not be possible. With two cabs, stacked, and corner loaded you may get 50hz. They are however very efficient and back in the day delivered a very impressive 80hz chest thump from kik drums
. I still own a working pair and use them in small rooms occasionally.
The MB1- I think that is the mid horn - might be a collectors item now to home theater horn lovers - kinda rare. But also easy to destroy the 12" cone driver (possibly 15"). Can't take much power at all below 200-250hz and the replacement speaker was the inverted dust cap model - unobtainium now.
MFX1 - I think is the hi horn? Uses the old 22-A 1" driver - needs the Peavey horn x-over or pad w/ cd horn eq to sound passable. At least this driver could be replaced with modern comparable if needed.
All in all it MIGHT be a fun thing to use if it's all good condition (a BIG if) - and you have room for it - and you like moving refrigerators
You could easily power it all with an old school cs800/cs400 combo using the "can" x-overs plugged into the back of the amps and sound decent. If you have a DSP speaker controller and know how to measure the speakers you could get it sounding fairly impressive - minus the deep bass folks are used to today.
That's what I remember anyways - have fun!