what is recommended for oil pressure monitoring? tapping in on the filter housing somewhere and running a line in the vehicle? If so, where would be the best place to tap in? at the sender?
or using the stocking sending unit and using a electronic gauge?

Mine is in my oil feed line to the turbo, which comes off the filtered side of the oil filter housing. I'd recommend anywhere on the filtered side, and depending on what ofh you're running there may be a spare port. You can always get some fittings to Tee off a port, or just ditch the stock oil pressure sending unit, since they're about as reliable a gauge as a boost gauge is at reading voltage.

The most accurate would probably be one of the oil feed ports on the head in reality, since thats the last place to get pressure and it will be the lowest there, so if its good there then you know its good everywhere else, most people just use the filter housing ports as mentioned already.

For safety of not vibrating or breaking a long fitting or sending unit, I tap off of the OFH and run a remote 12" line up to the spot behind the headlight and mount my sensor on the end of the hose, taking some stress off the housing. My son had a fitting down there break so we don't mount directly to the OFH anymore.

thank you