"...Did I say I was looking for more power?..."
No, you didn't, nor did you tell us the reason you want to use bi-wire and both taps. I was just guessing. Still am.
If you run both taps on most receivers, it will run the amp at half the impedance. Probably not a good idea on an old amp. There is really no need and you will not get any benefit out of it. The other thing to consider is that a better single run of cable will sound better than two runs of a lessor cable. I hope something I said helps but I'm still in the dark.
No, you didn't, nor did you tell us the reason you want to use bi-wire and both taps. I was just guessing. Still am.
If you run both taps on most receivers, it will run the amp at half the impedance. Probably not a good idea on an old amp. There is really no need and you will not get any benefit out of it. The other thing to consider is that a better single run of cable will sound better than two runs of a lessor cable. I hope something I said helps but I'm still in the dark.