Canister pump connections for tank ceiling

I have a 60 gallon acrylic tank that I am setting up. It has two large
predrilled holes in the top of the tank that I want to use for my
external canister filter. I can tell that I need bulkhead connectors.

When I look around on the net for bulkhead connectors, they usually the
suction filter screen / strainer is directly mounted to the bulkhead.
This is perfect for a back wall bulkhead, but not for a top bulkhead
mount like mine. I need the strainer to be an inch or so away from the
bulkhead to submerge it in water.

If this stuff were available at the Home Depot (it isn't), I could walk
in and try a few extensions, etc. until I had a set that fit. But on
the net, it is tough. I tried a couple of LFS. One didn't have
bulkhead connectors at all. The other kept trying to get me into a
different filter setup. I'm settled on a Eheim canister, and I want to
use that.

So, I can find a bulkhead connector and suction screen easy enough on
the net. Is there an extension that will fit? It would have to be like
a 1/2 FPT to 1/2 MPT to work (I think, I don't really know plumbing)

I would get a slip bulkhead, cut a piece of pipe to the size you need, and then
put a female or male X slip on the other end of the pipe depending on what your
screen is. The also have slip screens not threaded ones if you wanted to stay
slip the whole way thru.

aquariumpros.com has a good plumbing section
~John