Before you go through with this, you'll want to consider how much you work on the car and how often you use it. Hiding the harnesses means your access to things like the starter solenoid, switched 12-volt lead, mass air meter harness, and such will be limited. In fact, you'll need to pull the front wheels and inner fender liners out to get to them.
We've heard, and seen, people hide the rear harness, which travels across the firewall at the back of the engine. This usually involves some fabrication to get the harness to sit in the cowl area under the vent. It definitely cleans up the engine bay, but you'll need to cut some holes in the firewall to fish the harness in there. You'll most likely need to lengthen wires, and you have to have a way to keep the harness dry, as it'll be exposed to the elements in the cowl. Even though you may not drive your Pony in the rain, a simple car wash may be all it takes for the harness to short out. We simply pulled the harness from its plastic fasteners that hold it to the firewall, and tucked it down behind the engine.
With some careful planning and maneuvering, we were able to snake the right and left harnesses up in the fenderwells without lengthening any of them. We've heard of some people having to add wire to the headlight harnesses, but ours fit just right. With the wiring complete, we turned our attention toward the engine parts. As the motor went back together, we opted to replace our powdercoated Edelbrock Performer intake manifold with a polished Edelbrock Performer RPM II intake (PN 71231). The RPM II manifold is better suited to our stroked and supercharged combo, and the polished finish really lights up the engine compartment. Polished aluminum will require some maintenance, with frequent polishing a requirement to keep the finish from dulling. Water spots can also be troublesome, but if you keep it polished, they should come out fairly easily.
While you could spend some time--quite a bit in fact--sanding and buffing the factory aluminum valve covers, a much easier way to go about it is to order a set of chrome-plated covers (PN M-6582-D302) from Ford Racing Performance Parts. They have a slightly different finish compared to the polished intake, but they look great and save you from a lot of hand labor. Things like the air conditioning compressor bracket and alternator bracket were sanded and painted to give a fresh, shiny look. We also polished the supercharger brackets, since they were made from aluminum and had a relatively smooth finish to start with.
Getting down to the smallest of details, UPR provided us with its billet coolant reservoir, brake fluid, and window motor caps, along with its polished stainless radiator cover. We sprung for a chrome hood prop rod from Late Model Restoration, but you may want to go with a slightly cleaner look and get the gas struts to hold up your bonnet. These small items end up making a big impact in the overall look of your engine compartment.
Renovating your engine bay is a lot of work, but then any finish/detail work is. The good thing is your ride will stand above the rest because you went the extra mile that the other guy didn't.
 For the intake manifold, we...  For the intake manifold, we opted to make both a performance, and an appearance upgrade with the Edelbrock Performer RPM II. The RPM II has an increased RPM range over its Performer sibling that we were using, and the polished finish is just what this engine bay needed. |  Simple details like this timing...  Simple details like this timing pointer (PN M-6023-B351) from Ford Racing shows onlookers that you've put a lot of effort into this job. |  We repainted the water pump...  We repainted the water pump and associated brackets to give them a new appearance. The supercharger brackets were hand polished. |
 Here you can see the driver...  Here you can see the driver side wiring as it has been mounted in the inner fender. You need to mount it high enough so the fender liner will fit back in. |  The passenger side is routed...  The passenger side is routed in the same manner as the driver side. You can even mount the charcoal canister up here too. You just need to lengthen the vacuum hoses. |  Wire looms are an age-old...  Wire looms are an age-old way of cleaning up your engine compartment, and if you have a pushrod motor, these should be job one. Part number M-12297-B14 will get you these nice wire loom holders from Ford Racing Performance Parts. |
 Some wires will need to reappear,...  Some wires will need to reappear, but that doesn't mean they can't be hidden until you need them. This ground wire used to be mounted up on top where the prop rod is, but relocating it offered a cleaner, yet still effective, look. |  After a bit of polishing to...  After a bit of polishing to the top of the aluminum radiator, our makeover is complete. Yes, we could have gone quite a bit further, but we struck a balance between maintenance and appearance, that leaves us proud to display our supercharged powerplant anywhere, anytime. | |