Help with my 350?

I have a 98 Chevy truck that I love. I have had it about two years and I have done several off road goodies to it. I now have a problem with the stock 350 in it. It has started to drop  oil pressure. It reads a little over 40 when the motor is cold or accelorating. When the motor is warm and at idle it drops to about 20. It makes a little noise at idle when it drops to twenty. Help. I do not know engines. I want to keep the truck. What is the shape of the motor? How do I go about fixing it? Do I need to do something now or will it survive if I baby it?
                                Thanks  

20 at hot idle is not that bad at all.  Is the noise just a slight ticking or is it a harder sounds like possibly a rod bearing?  

I don't think the noise is all that loud. From inside the truck I can hear it if I have nothing on. From time to time it will make a rattling noise for a few seconds. What should I do? I want to rebuild but don't have the money. Will it survive a few months?  

The wrong but easy thing to do to prolong the life of the engine is to drop the pan and install a high volume oil pump.  Try that and start saving for a new engine.  

Hello I have a 99 Gmc sub,k1500 4x4, 350 Vortec Motor w/170,000k,w/ blown head gaskets, I do alot of hwy driven I am looking for a strong motor that fits my needs on & off road, Q: What is a good new motor or should I add all new profm.prts ?

please help!!!!  

1) Sometimes, what we think is an engine problem, is really just a guage or its wiring or its sensor going bad.

2) When you do an oil change, cut open the filter to see what's getting filtered.  Any pieces of metal in there?  Any pieces of metal in the oil itself? A bearing starting to go bad may cause a drop of pressure and some noise, but I'll bet its not the problem--you'd be hearing more noise, and soon.

3) If you don't have a medical stethoscope (who does?), grab a long metal rod or screwdriver, put your thumb over the end, and while the engine is running, put the other end on various parts of the engine.  Watch out for the fan and belts, of course, but if something's going, its gonna vibrate, and you'll notice a different sound coming up that long rod or screwdriver.  It may be the sound you're hearing is something else, a waterpump going or who knows what.  Or maybe you'll find out the sound is one of the valvesprings starving for oil when pressure is low, but goes away once the pressure comes back.

But, maybe none of these ideas will work.  Babying an engine never hurts--who wants to make the $3000 decision to replace an engine or make a downpayment on something new?  Its probably best to go to a mechanic and have it looked at...but unfortunately, finding a good mechanic these days is like finding a good doctor or a good lawyer.