i had some big issues with things not working
and me checking for a blown fuse. that looked fine , but wasn't
our cars have 15+ year old fuses in them.
anyway i decided to replace all of them with new fuses.
i found something interesting
they are called smart fuses
and they have a diode installed. since electricity always flows the
way with the least resistance, the diode won't light up , unless the fuse is blown. it's genius and simple.
the only thing that might suck is the fact that current has to be flowing for the diode to light.
but if it is an important circuit i am sure it would get a power feed.
they are twice as much as normal fuses, but i think well worth it.
http://www.littelfuse.com/searchresults.html?NN=0%3AAcquired+Brand%3A259

I like suggestion of replacing all the old fuses with oem's, IMO! 1 test light is enough.

replaced them all with new style BUSS fuses. The diode is a good idea, but definately not worth the money, all you need is a test light, and if you own one of these cars, you should already have at least one of those in the toolbox....

i do...lol

DVOM i think in our case is better.
digital volt ohm meter