Whatever you do, do something. If the line on the mechanical gauge lets go without an isolator in it, you'll have diesel fuel being sprayed into the passenger compartment. Either an isolator, or an electric gauge are preferable to the current set up.

 

I run a grease gun hose from the top of the filter, no fluctuation, steady guage.

 

explain please. are you threading grease gun hose into filter and then attaching fuel line going to gauge to the other end of the hose or ??

 

Herb,
Check out genos garage, they sell the "grease gun" fuel hose

http://198.104.149.53/CoastalData/sh...D=1747&CATID=1

 

The '99 fuel filters have a pipe plugged port to connect a fuel pressure line...the '01's don't.
The fuel pressure kit, the grease gun line extensions, the fittings, the needle valve and the thread sealant were all at my local Autozone (I don't like givin'em free advertize but ...).
All the trouble of a simple fuel pressure guage could/should be solved w/cheap guage kit with the proper fittings.