Nylon is relatively straightforward. I got everything but the unions from a junkyard including both 5/16 and 3/8 nylon and steel quick disconnects for each end.
You'd need a tubing cutter to be able to cut the steel lines, a box cutter to cut the nylon, boiling water to bend the nylon, and some wrenches for the brass compression unions. Check out McMaster Carr if you don't like to use brass compression unions, 5/16 and 3/8 are the sizes you will need.
Starting at the engine, there is a steel line at each end of the fuel rail, the 3/8 line is the feed and the 5/16 the return. You'd cut them right at the throttle body immediatly before the bend down towards the exhaust. The open lines would be pointing directly toward the fender. On the end of these you use a compression fitting to splice on a short section of line that has a 'Quick connect' fitting. It looks like this (Dorman has a blister pack with two of them, 800-159, has everything you'd need):
Then on the end of that newly installed fitting you have the nylon piece that connects to it. You want a piece that has a length of tube pre-installed:
Next you need a push to connect fitting, Dorman again # 800-191 ; 800-193. This allows you to connect two pieces of nylon line together,
with no hassle, and no restriction to flow. The ends of the nylon tube need to be cut straight though. Keep the nylon away from the exhuast, it should route with an easy curve down along the path the brake lines follow, nothing like it did with the steel line before.
Then the long length of tube back to the tank, secured to the body/frame every so often, there are other methods if the OEM plasting mounts are totally messed up. The fitting at the tank is the same as the fitting at the engine. Put the union on the straight section of line that is right before the turn down. For the Fuel filter, all you need is a push to connect and the appropriate nylon end. You can put it anywhere you want, as long as you secure it to the body/frame. The '93 H-body filter uses the quick-connects so is perfect for this.
Parts needed, all of which can be sourced new:
5/16" line (25 ft, you will use about 14 ft depending on how you route the lines) ($25)
3/8" line (25 ft, same usage as above) ($25)
5/16 push to connect (x2) ($8 for 2)
3/8 push to connect (x4) ($16 for 4)
'93 LeSabre fuel filter ($5)
5/16 compression union (x2) ($5 or so)
3/8 compression union (x2) ($5 or so)
5/16 steel quick connect end (x2)
3/8 steel quick connect end (x2) ($20 800-159)
5/16 nylon quick connect end (x2) ($20 each)
3/8 steel quick connect end (x2) ($20 each)
Being thrifty puts the repair under $30 depending on local pricing and if you have a u-pull yard with everything you need. I'd budget $100 though. The stuff marked in blue can come from a junkyard, they are mostly at the connection to the fuel tank area on the passenger side of the '92+ H-body cars, the Dorman 'kits' are way overpriced IMO. Steel vs. Nylon are about the same cost for the tubing. If cost is a big factor, you can take the entire sending unit with fuel pump, nylon lines, etc. from the '92-'95 H-body ('96+ have a different fuel level sensor) and only need to buy the fuel filter, push to connect and compression unions new.
