A couple of folks here have installed pressure gauges. Roller bearing engines need plenty of flow but not a lot of pressure, so it is only going to be something around 10 psi or less.

Camperman, this old post provides some details on my oil pressure gage installation.  After living with the pressure gage for several years I have noted that my previously reported pressure data was a bit on the low side.  Depending on the weight of oil, I run about 4.5 to 6.0 psi on the freeway, still zero psi at idle.  I like having the gage.  

http://suzukisavage.com/cgi-bin/YaBB.pl?num=1559853083

It's working well.  The gage is holding up and so is the nylon tubing.  If you want more details on the parts, shoot me a PM and I will dig up all the part numbers for you.  

For my larger engine, I moved the gage connection.  I prefer the new location.  This old post provides details on the new location for the gage connection.

http://suzukisavage.com/cgi-bin/YaBB.pl?num=1596951230

Hope this helps.  Best regards, Mike