If you can find out the crossover frequency of the Mani-2's you can come close, i'm not sure how good it would be. you would need to put your F25 behind your preamp, find the crossover frequency of the Mani-2's run your F-25 out to your amps, probably around 2K (you will need this frequency).
I looked at a frequency chart online for the Mani-2's, they appear to be using LR4 slopes. The Accuphase uses Gaussian, so right off the bat, you will have a passive network using one type crossover slope and an electronic using another. If you really want to do this, I recommend that you just get the drivers, make your own boxes without crossover units and use the Accuphase equipment. The Forest Drivers are available, I have impedence curves for them, you would need to put a compensation network inline with no filters, then you can use the Accuphase stuff, the results would be outstanding. Really what you are trying to do is possible, but impractical.
I looked at a frequency chart online for the Mani-2's, they appear to be using LR4 slopes. The Accuphase uses Gaussian, so right off the bat, you will have a passive network using one type crossover slope and an electronic using another. If you really want to do this, I recommend that you just get the drivers, make your own boxes without crossover units and use the Accuphase equipment. The Forest Drivers are available, I have impedence curves for them, you would need to put a compensation network inline with no filters, then you can use the Accuphase stuff, the results would be outstanding. Really what you are trying to do is possible, but impractical.