Larry, PCV is not a huge inpact on wiper operation, low engine vacuum under load slows them down. I have two bone stock 261 engine I pulled as runners, a '59 and a 55.1, both with factory PCV system. Vacuum port on intake manifold below carb has a brass connector with ports for PCV, brake booster & also wipers via the vacuum pump on the older one.
Do you have combo fuel / vacuum pump? That was there to assist the wipers under lo engine vacuum. If you don't get one! Other options include adding a vacuum storage tank with a check valve (but sooner of later you run low on vacuum on long hard pulls) or electric vacuum pump.
