hello Patrick

Im no expert on these things but i'd say the walbro pump you have is more than upto the job, but and this is something im doing very soon, if you know somebody locally who can put you a direct 12volt feed from the battery to pump get it done So many pumps dont have 12volts at them as the wiring is old, in your case 15 years old and due to the age and other powered items the loom supplies sometimes you may be at full/mid power and your car will run lean without you knowing it due to the pump voltage so if you can get this done mate please do.

Sorry i cant help you on your other question but whilst we're both at a similar position thought i'd help you wher i can