I would like to do the same. If you figure it out, maybe you could update this thread. I haven't had any luck with my occasional random searching.
This is really irrelevant for P2Pool because p2pool forwards blocks among the p2pool miners and has them all forward it in. This works really well because the p2pool forwarding is much faster than the bitcoin forwarding because it has to do less validation work.
Actually having large numbers of connection on the daemon you're mining from is a bad idea because servicing large numbers of mostly useless random windows users will slow down the daemon you need to be responding promptly to process blocks and mine.
In my P2pool operation I run four bitcoin daemons: Two service p2pool nodes and only connect to my own nodes and a couple of carefully selected large miner daemons. One is a regular listening public node (with simply maxconnections=512, no crazy patches and it now has 489 connections), the other is a hidden unannounced node on secondary connectivity for dos resistance.
This is the sort of setup you want for reliable mining. Not some connection spammy patch.