As far as fuel, 87 octane is fine unless you advance the timing a good bit or change out your cylinder heads or pistons.
The lights in the dash are a bit of a pain to do,
First disconnect the battery; then, you'll need to pull the headlight switch knob out by first pushing in on the little button on the side of the switch inside the dash (this is by far the hardest part...) and then pulling on the knob... it probably won't want to come out, you'll have to spent time fighting with it, get ready for a really sore arm and finger(s) from this one.
Next, unscrew the headlight switch bezel piece from the switch (little round chrome piece that goes through the dash) and remove all of the screws from the instrument cluster bezel; carefully remove the bezel.
Now, remove all the screws holding the lense and cluster in place.
This is the next tricky part: reach through from under the dash and squeeze on the widest parts of the speedometer cable and work it off the back of the speedometer... remember, it's probably been there 30+ years without being removed, it WILL NOT want to come loose.... get ready for some bruised knuckles when it does come off. Then, do the same thing for the large electrical connector that goes into the back of the cluster.
You can now replace all of your bulbs by twisting out the little black lamp holders from the back of the cluster, be careful with this, as the plastic of the cluster is more than likely VERY brittle from age, and the thin film that has the circuits printed on the back is VERY flimsy and easily torn.
Installation is pretty much reverse of removal... except you just shove the headlight knob back in, you don't have to fuss with that button again... pretty relieved about that one huh?
__________________ 1976 Ford Mustang II Ghia: 302 with a 600cfm Edelbrock carb, Edelbrock Performer 289 intake, Dynomax Blackjack headers, 2.5" exhaust with Flowmaster Super 44s. RJS 11-gallon fuel cell, C4 tranny, chrome 16" pony wheels, fuzzy dice, brown vinyl half-top, and painted in the tackiest color ever (harvest gold, that's why I call it "The Goldenrod").
Also have a 2003 Dodge Ram (lightly modded daily driver/tow rig/office/dining room/home away from home/workshop... I call it "The Big Blue Dawg".) | 
