[#welcome] to the forum Paul! I really don’t have a clue about those fuel tanks but I’ll see what I can find. No promises though, lol.
This link shows a potential loadout diagram:
http://www.aerospaceweb.org/question/planes/q0105.shtml
Also, check this out:
F-22 Carriage Capability
The F-22’s combat configuration is “clean”, that is, with all armament carried internally and with no external stores. This is an important factor in the F-22’s stealth characteristics, and it improves the fighter’s aerodynamics by dramatically reducing drag, which, in turn, improves the F-22’s range. The F-22 has four under wing hardpoints, each capable of carrying 5,000 pounds. A single pylon design, which features forward and aft sway braces, an aft pivot, electrical connections, and fuel and air connections, is used. Either a 600-gallon fuel tank or two LAU-128/A missile launchers can be attached to the bottom of the pylon, depending on the mission.
There are two basic external configurations for the F-22: Four 600 gallon fuel tanks, no external weapons: This configuration is used when the aircraft is being ferried and extra range is needed. A BRU-47/A rack is used on each pylon to hold the external tanks. Two 600 gallon fuel tanks, four missiles: This configuration is used after air dominance in a battle area has been secured, and extra loiter time and firepower is required for Combat Air Patrol (CAP). The external fuel tanks, held by a BRU-47/A rack are carried on the inboard stations, while a pylon fitted with two LAU-128/A rail launchers is fitted to each of the outboard stations. An all-missile external loadout (two missiles on each of the stations) is possible and would not be difficult technically to integrate, but the Air Force has not stated a requirement for this configuration.
The LAU-128/A rail launcher is the standard rail launcher used today on the F-15 and can carry either of the missiles used on the F-22, AIM-120 AMRAAM or AIM-9 Sidewinder. However, both missiles carried on the fire missile adapter configuration for F-22 must be the same type for aircraft weight and balance considerations. The 600-gallon fuel tanks are similar to the same external tanks that are used on the current F-15 Eagle. However, a new tank is being developed that has baffles in it to prevent the fuel from sloshing. This gives the tank better center of gravity control, which allows for safe jettisoning of the tanks. The BRU-47/A rack is not the same type of rack that is used internally on the F-22 to carry the GBU-32 1,000-pound class Joint Direct Attack Munition (JDAM), although they are similar and both are currently in use. However, there are no plans to carry JDAM externally on F-22. The BRU-47 will only be used to hold the external fuel tanks.
The pylon itself is designed for minimal impact on aircraft performance. If it becomes necessary for the pilot to jettison the external stores, the entire pylon is jettisoned along with the tank or missile launch rails. The pylon has an aft pivot, so when the stores are jettisoned, the forward attach point is released first, the pylon rotates on the pivot, and then the aft pivot is released. This motion allows the pylon, along with the tank or launch rail to clear the aircraft when it is released into the slipstream.
I haven’t found any pics of a Raptor actually carrying fuel tanks, so maybe aerodynamic testing of this configuration hasn’t taken place yet? Or maybe, they just think it doesn’t look glamorous, lol. Well, I hope this helps some. Good luck on your build.